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Home My WebLink AboutMS 07-11; 3053 OCEAN STREET; PRELIMINARY GEOTECHNICAL INVESTIGATION PROPOSED IMPROVEMENTS TO OCEAN STREET PROPERTY; 2007-12-27CONSTRUCTION TESTING & ENGINEERING, INC. SAN DIEGO, CA RIVERSIDE, CA VENTURA, CA TRACY, CA SACRAMENTO, CA 1441 Montiel Road 14538 Meridian Parkway 1645 Pacific Avenue 242 W. Larch 3628 Madison Avenue Suite 115 Suite A Suite 107 Suite F Suite 22 Escondido, CA 92026 Riverside, CA 92518 Oxnard, CA 93033 Tracy, CA 95376 N. Highlands, CA 95660 (760) 746-4955 (951) 5714081 (805) 486-6475 (209) 839-2890 (916) 331-6030 (760) 746-9806 FAX (951) 5714188 FAX (805) 486-9016 FAX (209) 839-2895 FAX (916) 331-6037 FAX PRELIMINARY GEOTECHNICAL INVESTIGATION PROPOSED IMPROVEMENTS TO OCEAN STREET PROPERTY 3053 OCEAN STREET CARLSBAD, CALIFORNIA RECEIVED PREPARED FOR: MR. TONY CASSOLATO 576 CAMINO ELDORADO ENCINITAS, CALIFORNIA 92024 DEC 282007 CITY OF CARLSBAD PLANNING DEPT 12a:3 z3a;(4316 CONSTRUCTION TESTING & ENGINEERING, INC. 1441 MONTEIL ROAD, SUITE 115 ESCONDIDO, CALIFORNIA 92026 CTE JOB NO. 10-8790G DECEMBER 27, 2007 GEOTECHNICAL • ENVIRONMENTAL • CONSTRUCTION INSPECTION AND TESTING • CIVIL ENGINEERING • SURVEYING TABLE OF CONTENTS Section Page 1.0 EXECUTIVE SUMMARY .1 2.0 INTRODUCTION AND SCOPE OF SERVICES ....................................................................2 2.1 Introduction....................................................................................................................2 2.2 Scope of Services...........................................................................................................2 3.0 BACKGROUND INFORMATION ..........................................................................................3 3.1 Site Location and Description........................................................................................3 3.2 Proposed Improvements.................................................................................................4 4.0 FIELD AND LABORATORY INVESTIGATION ..................................................................4 4.1 Field Investigations........................................................................................................4 4.2 Laboratory Investigation................................................................................................5 5.0 GEOLOGY................................................................................................................................5 5.1 General Physiographic Setting.......................................................................................5 5.2 Geologic Conditions ......................................................................................................6 5.2.1 Topsoil/Fill Soils...................................................................................................6 5.2.2 Quaternary Terrace Deposits ................................................................................7 5.3 Groundwater Conditions................................................................................................7 5.4 Geologic Hazards...........................................................................................................8 5.4.1 Local and Regional Faulting.................................................................................8 5.4.2 Site Near Source Factors and Seismic Coefficients .............................................. 9 5.4.3 Tsunami, Seiche, and other Storm Wave Damage .............................................10 5.4.4 Landsliding or Rocksliding.................................................................................11 5.4.5 Compressible and Expansive Soils.....................................................................11 5.4.6 Liquefaction Evaluation......................................................................................11 5.4.7 Seismic Settlement Evaluation ...........................................................................12 5.4.8 Corrosive Soils....................................................................................................12 5.4.9 Bluff Erosion and Setbacks.................................................................................13 6.0 CONCLUSIONS AND RECOMMENDATIONS ..................................................................13 6.1 General.........................................................................................................................13 6.2 Site Preparation............................................................................................................14 6.2.1 General................................................................................................................14 6.2.2 Site Excavations..................................................................................................15 6.2.3 Fill Placement and Compaction..........................................................................15 6.2.4 Fill Materials.......................................................................................................16 6.3 Temporary Construction Slopes ..................................................................................16 6.4 Foundations and Slab Recommendations....................................................................17 6.4.1 General................................................................................................................17 6.4.2 Spread Foundations, Soldier Beams and Slabs-on-Grade ..................................17 6.4.3 Foundation Settlement........................................................................................19 6.5 Lateral Resistance and Earth Pressures........................................................................19 6.6 Exterior Flatwork.........................................................................................................21 6.7 Vehicular Pavements ...................................................................................................21 6.8 Drainage.......................................................................................................................22 6.9 Slopes...........................................................................................................................23 \\Cte_scrvciprojects\I 0-8001 to 10-9000 Projccts\I 0-8790G\Rpt_Geotech.doc 6. 10 Construction Observation .23 6.11 Plan Review...............................................................................................................24 7.0 LIMITATIONS OF INVESTIGATION..................................................................................24 FIGURES FIGURE 1 INDEX MAP FIGURE 2 EXPLORATION MAP FIGURE 3 REGIONAL FAULT AND SEISMICITY MAP APPENDICES APPENDIX A REFERENCES CITED APPENDIX B EXPLORATION LOGS APPENDIX C LABORATORY METHODS AND RESULTS APPENDIX D STANDARD SPECIFICATIONS FOR GRADING \\Ctc_scrvcr\projccts\I 0-8001 to 10-9000 Projccts\I 0-87900\Rpt_Geotcch.doc Preliminary Geotechnical Investigation Page 1 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 CTE Job No. 10-8790G 1.0 EXECUTIVE SUMMARY Our investigations were performed to provide site-specific geotechnical information for the construction of the proposed improvements to the property located at 3053 Ocean Street in Carlsbad, California. The proposed development is considered feasible from a geotechnical standpoint provided that recommendations in our report are implemented. Based on our observations and reference review, soils beneath the site consist of approximately one to three feet of undifferentiated topsoil/fill soils overlying Quaternary Terrace Deposits. Grading of the site is expected to be minimal. Due to the different depths at which Quaternary Terrace Deposits are found, there is approximately three feet of fill on the west side of the site and one foot of fill on the east side of the site. Groundwater was encountered during our investigation of the site at approximate elevations ranging between 11 to 13 feet above mean sea level. These elevations may represent a perched groundwater level at the base of the Quaternary Terrace deposits. During seasonal weather changes, areas of local saturation may be encountered. However, from a review of preliminary project plans, we do not anticipate that groundwater will affect the proposed development, provided appropriate surface drainage is developed and/or maintained. Based on the geologic findings and referenced review, no active surface faults are known to exist at the site. In general, the results of our review indicate that the proposed project can be constructed as planned provided the recommendations presented in this report are followed. Cte_servcr\projects\I 0.800 I to 10-9000 Projects\I 0-87900\Rpt_Geotcch.doc Preliminary Geotechnical Investigation Page 2 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 CTE Job No. 10-8790G 2.0 INTRODUCTION AND SCOPE OF SERVICES 2.1 Introduction Construction Testing and Engineering, Incorporated ("CTE") has prepared this preliminary geotechnical report for the site located at 3053 Ocean Street in Carlsbad, California, as shown on the general site location map (Figure 1). It is our understanding that the proposed development will consists of the construction of multi-story condominiums/townhouses and associated improvements. The bottom level of the structures is also anticipated to be partially subterranean. Demolition of the existing structures will be performed to allow for construction of the proposed development. Our investigation included filed exploration, laboratory testing, geologic hazard evaluation, geotechnical engineering analysis, and preparation of this report. This report presents the results of our preliminary geotechnical investigation and provides conclusions and recommendations for the excavations, temporary shoring, fill placement, and foundations for proposed development. Cited references are presented in Appendix A, logs of borings are presented in Appendix B, laboratory methods and results are presented in Appendix C, and standard specifications of grading are presented in Appendix D. 2.2 Scope of Services Our scope of services included: Review of readily available geologic reports pertinent to the site and adjacent areas. Explorations to determine subsurface conditions to the depths influenced by the proposed construction. Laboratory testing of representative soil samples to provide data to evaluate the geotechnical design characteristics of the site foundation soils. Definition of the general geology and evaluation of potential geologic hazards at the site. \Cte_serveiprojccs\l 0-8001 to 10-9000 ProjcctsI 0-8790G\Rpt_Gcotcch.doc Preliminary Geotechnical Investigation Page 3 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 CTE Job No. 10-8790G Preparation of this report detailing the investigation performed and providing conclusions and geotechnical engineering recommendations for design and construction. 3.0 BACKGROUND INFORMATION 3.1 Site Location and Description The site is located on the west side of Ocean Street in Carlsbad, California, on a coastal bluff terrace overlooking the adjacent coastal beach and Pacific Ocean. The coastal buff and bluff face in this area has been previously modified by the construction of residential buildings and beach access routes. As such, the City of Carlsbad has restricted proposed new development from seaward encroachment in this area by establishing "string lines" to delineate the western limits of development of new structures and associated improvements such as decks, pools, and patios along the coastal bluff. The string lines have been established based on the western extent of existing structures on adjacent and other nearby lots in the vicinity of the subject site. The existing structure at the subject site is situated within the eastern portion of a roughly rectangular shaped parcel that slopes down slightly to the west. The site ranges in elevation from approximately 44 feet above mean sea level at the eastern limits, to approximately 27 feet above mean sea level at the western limits. This area is east of the established string line for existing structures, as shown on Figure 2. A modified coastal bluff face is present westward of the structural string line, and has a vertical relief of approximately 15 feet. The coastal bluff face intersects the present coastal beach at the approximate elevation of 12 feet above mean sea level in the most western portion of the parcel. The approximate configuration of the site, including \\Cte_scrver\projects\I 0-8001 to 10-9000 Projects\I 0-8790G\Rpt_Geotech.doc Preliminary Geotechnical Investigation Page 4 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 CTE Job No. 10-8790G the existing structure, associated improvements, and site topography are shown on the Site Exploration Map, Figure 2. Land use near the site consists of residential properties. The north and south sides of the site are bound by existing residences, the west side by the Pacific Ocean, and the east side by Ocean Street. 3.2 Proposed Improvements We understand that the proposed development/project will include the demolition of most or all existing improvements and the subsequent construction of multi-story condominiums/townhouses (upon a partially subterranean bottom level) and associated improvements. Associated improvements may include parking and drive areas, utilities, decks, stairways, patios and landscaping areas. We understand the proposed improvements will be located in the same general area of the existing improvements and within the limits allowed by the appropriately established string lines. 4.0 FIELD AND LABORATORY INVESTIGATION 4.1 Field Investigations Field investigations at this site, performed on February 14, 2007 and August 27, 2007, included site reconnaissance and excavation of two soil borings and five shallow test pits. Soils were logged and visually classified in accordance with the Unified Soil Classification System by our field geologist. The field descriptions have been modified, where appropriate, to reflect laboratory test results. The boring logs include descriptions of the soil, in situ field-testing data, \Ctc_servcr\projects\I 0-8001 to 10-9000 Projccls\I 0-8790(ARpt_Geotech.doc Preliminary Geotechnical Investigation Page 5 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 CTE Job No. 10-8790G and supplementary laboratory data, and are included in Appendix B. Figure 2 is a map showing the approximate locations of the boring explorations conducted by this firm. 4.2 Laboratory Investigation Specific laboratory tests conducted for this investigation included: grain size analysis, In-Place Moisture and Density, maximum density/Modified Proctor, consolidation and chemical analysis. Test method descriptions and laboratory results are presented in Appendix C. 5.0 GEOLOGY 5.1 General Physiographic Setting San Diego is located within the Peninsular Ranges physiographic province that is characterized by its northwest-trending mountain ranges, intervening valleys, and predominantly northwest trending active regional faults. The San Diego Region can be further subdivided into the coastal plain area, a central mountain—valley area and the eastern mountain valley area. The project site lies within the coastal plain area of low relief that slopes gently toward the Pacific Ocean. The coastal plain is characterized by geomorphic landforms known as marine terraces, which are erosion surfaces or abrasion platforms cut by ocean —wave processes along past coastlines. These surfaces are recognized today as the relatively flat-lying mesas and terraces that range in elevation across the coastal plain of San Diego. The elevation differences of these marine terraces are the result of sea level changes that are associated with glacial retreat and advance throughout the Pleistocene, and uplift associated with activity on the Rose Canyon Fault Zone over the past two million years. The mesas or terraces have been incised by westward flowing drainages that have adjusted to the relative sea level changes in elevation. The combined effect \\Cte_scrvcr\projects\10-8001 to 10-9000 Projccts\I 0-8790G\Rpi_Gcotcch .doc Preliminary Geotechnical Investigation Page 6 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 CTE Job No. 10-8790G of these processes is that older marine terraces are found at progressively higher elevations. Several distinct marine terraces present in the San Diego area include the Linda Vista Mesa (cut approximately 1.3 million years ago), the Nestor Terrace (cut approximately 120,000 years ago), and the Bird Rock Terrace (cut approximately 80,000 years ago). The marine terraces are typically covered with marine sediments covered with non-marine terrestrial deposits. Specifically, the site is situated on a Pleistocene marine terrace with terrace deposits that have been correlated with the Pleistocene Bay Point Formation; the terrace has been incised by the Aqua Hedionda Lagoon drainage basin to the south and the Buena Vista Lagoon drainage basin to the north. The western portion of the site is covered with Holocene beach deposits. 5.2 Geologic Conditions Based on mapping compiled by Tan and Kennedy (1996), surface soils near the site consist of Quaternary Terrace Deposits. Based on our explorations, surface and near surface soils are consistent with the mapping completed by Tan and Kennedy, with relatively thin topsoil and artificial fill soils that overly the Quaternary Terrace Deposits. It is anticipated that units of the Tertiary Santiago Formation underlie the Terrace Deposits at depths greater than the maximum explored depth of 31.5 feet. The soil descriptions below are based on qualitative and quantitative attributes of the soils encountered at the site. 5.2.1 Topsoil/Fill Soils These soil types were encountered to depths ranging from approximately one foot to three feet below existing grades. These materials were observed to consist primarily of loose to medium dense, moist, medium brown, to dark brown silty sand to poorly graded VCtc_scrvcr\projccis\I 0-8001 to 10-9000 Projccts\I 0-8790G\Rpt_Gcotech.doc Preliminary Geotechnical Investigation Page 7 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 S CTE Job No. 10-8790G sand with silt, with organics and locally cobble sized clasts. Fill materials will require preparatory grading prior to construction of the proposed improvements as recommended herein. 5.2.2 Quaternary Terrace Deposits Quaternary terrace deposits were observed beneath site fill soils to the maximum depth explored. These materials generally consist of brown, moist, medium dense to very dense, poorly graded sand to silty fine- to medium-grained sands, with locally coarse grained sands and fine gravels. These native materials are suitable for support of the proposed improvements as recommended herein. 5.3 Groundwater Conditions Groundwater was encountered during our explorations in B-i at approximately 31.5 below existing grade, or approximately 12.5 feet above mean sea level, and in B-2 at approximately 20 below existing grade or approximately 13-feet above mean sea level. These observed depths to groundwater during drilling may represent a slightly perched groundwater layer situated at the base of the Pleistocene Terrace Deposits and the underlying Tertiary Santiago formation deposits. We anticipate permanent groundwater is located at an approximate elevation of zero to three feet above mean sea level, and may vary with tidal fluctuations. Although groundwater levels may fluctuate and could affect construction, groundwater is not expected to affect the proposed development if proper drainage is maintained and the recommendations herein are incorporated in the design and construction of the project. \\Cte.server\projects\10-8001 to 10-9000 Projects\I 0-8790G\Rpt_Geotech.doc Preliminary Geotechnical Investigation Page 8 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 CTE Job No. 10-8790G 5.4 Geologic Hazards The following paragraphs discuss geologic hazards that are pertinent to the site and an assessment of any potential impacts. 5.4.1 Local and Regional Faulting Based on our site reconnaissance, evidence from our explorations, and a review of referenced literature, no known active fault traces underlie or project toward the site. In, addition, the site is not located within an Aiquist —Priolo Earthquake Fault Zone or within any regulatory fault zones define by the City of Carlsbad. According to the California Division of Mines and Geology, a fault is active if it displays evidence of activity in the last 11,000 years (Hart and Bryant, 1997). The California Geological Survey broadly groups faults as "Class A" or "Class B" (Cao and others, 2003). Class A faults are identified based upon relatively well constrained paleoseismic activity, and a fault slip rate of more than 5 millimeters per year (mm/yr). In contrast Class B faults have comparatively less defined paleoseismic activity and are considered to have a fault slip rate less than 5 mm/yr. The nearest known Class A fault to the site is the Temecula segment of the Elsinore Fault which is approximately 39.6 kilometers northeast of the site. The closest Class B fault is the Rose Canyon Fault which is approximately 7.6 kilometers west of the site. Following Table 1 presents the six nearest faults to the site, include magnitude and fault classification. Attached Figure 3 shows regional faults and seismicity with respect to the site. \\Cie_sen'er\projccts\I 0-8001 to 10-9000 Projects\I 0-87900\RpLo3cotcch.doc Preliminary Geotechnical Investigation Page 9 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 CTE Job No. 10-8790G TABLE 1 NEAR SITE FAULT PARAMETERS FAULT NAME DISTANCE FROM SITE (MILES) MAXIMUM EARTHQUAKE MAGNITUDE CLASSIFICATION Rose Canyon Fault 7.6 7.2 B Newport-Inglewood (offshore) 7.8 7.1 B Coronado Bank 33.2 7.6 B Elsinore Temecula 39.6 6.8 A Elsinore-Julian 40.1 7.1 A Elsinore-Glen Ivy 54.2 6.8 A California Geologic Survey, Probabilistic Seismic Hazards Mapping Ground Motion Page (on line pshamap.asp) indicates ground motions with 10% probability of exceedance in 50 years for the site as underlain by alluvium type materials are as follows: TABLE 2 SITE GROUND MOTION WITH 10% PROBABILITY OF EXCEEDANCE IN 50 YEARS PARAMETER UNIT GRAVITY Ground Acceleration 0.34 Spectral Acceleration at Short (0.2 second) Duration 0.815 Spectral Acceleration at Long (1.0 second) Duration 0.409 5.4.2 Site Near Source Factors and Seismic Coefficients In accordance with the 2001 California Building Code, Volume 2, Figure 16-2, the referenced site is located within seismic zone 4 and has a seismic zone factor of Z=0.4. The nearest active fault, the Rose Canyon Fault Zone, is approximately seven kilometers to the west and is considered a Type B seismic source. Based on the distance from the site to the Rose Canyon Fault Zone, near source factors of N=1.1 and Na=l.O are \\Cte_server\projects\10-8001 to 10-9000 Projccts\I 0-8790G\Rpt..Geotcch .doc Preliminary Geotechnical Investigation Page 10 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 CTE Job No. 10-8790G appropriate. Based on the shallow subsurface explorations and our knowledge of the area, the site has a soil profile type of SD and seismic coefficients of Cv=0.74 and Ca=0.44. 5.4.3 Tsunami. Seiche, and other Storm Wave Damage The potential for tsunami damage at the can not be precluded, based on the site's location adjacent to the Pacific Ocean and elevations ranging from approximately 11 feet to 44 feet above sea level. The approximate elevations of the site east of the established structural string line range from 27 feet to 44 feet above mean sea level. The elevations on the site area delineated for associated improvements, such as decks and patios ranges between 22 feet to 27 feet above mean sea level. The remainder of the site consists of vegetated slopes leading to the coastal beach. According to McCullough (1985) the potential for 100 and 500 years tsunami events is four and six feet. This suggests that there is a very low probability of site damage to the portions of the site above the 22 foot elevation where the structures and associated improvements are permitted. Seismically induced seiche (oscillatory waves) damage is also considered unlikely for the reasons stated above. Aerial and surface photographs of the site and surrounding area were reviewed to help re- construct the site development history and provide a relative correlative of sea cliff erosion due to storm wave damage. Oblique aerial photographs were collected from the California Coastal Records Project (www.californiacoastline.org), of the Ocean Street \Ctc_servc?projcctsI 0-800 I to 10-9000 Projecls\I 0-8790G\Rpt_Geotcch.doc Preliminary Geotechnical Investigation Page 11 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 CTE Job No. 10-8790G area from 1972, 1979, 1987, 1989, 2002, 2004, and 2006. Several serve winter storms occurred over this time period, specifically in 1978, 1982 and 1992. Review of these photographs indicate that the coastal bluffs in the area of Ocean Street have remained relatively stable and exhibited no signs of significant wave damage or erosion from 1972 to present. 5.4.4 Landsliding or Rocksliding According to Tan and Giffen (1995), the site area along the coastal bluff is considered most susceptible to landsliding. Minor slumping or block falls may be expected within steeper sections of the bluff west of the established string lines. However, we did not observe active landslides or rockslides at the site, and landslides have not been mapped near the site area (Tan and Kennedy, 1996). Therefore, we anticipate that the potential for landsliding or rocksliding to affect the site during its design life is negligible. 5.4.5 Compressible and Expansive Soils Based on geologic observation and laboratory testing of onsite soils, the fill materials generally exhibit low to moderate compressibility and low expansive characteristics (El less than 30). Compressible fill materials will be mitigated via overexcavation and recompaction or removal to facilitate the partially subterranean improvement level. Underlying native materials are generally non-compressible and non-expansive. Therefore, these materials are considered suitable for support of proposed improvements. 5.4.6 Liquefaction Evaluation Liquefaction occurs when saturated fine-grained sands or silts lose their physical strength during earthquake-induced shaking and behave as a liquid. This is due to loss of point- \\Cte_scrver\projccis\I 0-800 I to 10-9000 Proj ecLs\I 0-8790GRpt.Geotech.doc Preliminary Geotechnical Investigation Page 12 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 CTE Job No. 10-8790G to-point grain contact and transfer of normal stress to the pore water. Liquefaction potential varies with groundwater level, soil type, material gradation, relative density, and the intensity and duration of ground shaking. The potential for damage to the site from liquefaction of site soils east of the established string lines is considered low. This is based on the depth to groundwater and the generally medium dense to dense nature of underlying native soils in the area. 5.4.7 Seismic Settlement Evaluation Seismic settlement occurs when loose to medium dense granular soils densify during seismic events. We anticipate that topsoils and/or loose or soft surficial soils will be mitigated during site grading/excavation. The upper 10 to 15 feet of native materials at the site were generally found to be medium dense, but may experience minor and tolerable seismic settlement. The foundation recommendations herein are anticipated to adequately accommodate the minor seismic settlement. Therefore, the potential for seismic settlement resulting in significant structural damage to site improvements should be considered low. 5.4.8 Corrosive Soils Based on the representative soil sample submitted for chemical analysis, the onsite soils are anticipated to have a low potential to corrode Portland Cement concrete based on sulfide content, and a low potential to corrode ferrous metals based on chloride content and soil resistivity. CTE does not practice corrosion engineering. Therefore, a corrosion \\Cte_server\projccts\I 0-800 I to 10.9000 Projecls\I 0-87900\Rpt_Geotech.doc Preliminary Geotechnical Investigation Page 13 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 CTE Job No. 10-8790G specialist could be consulted if additional investigation and/or evaluation are deemed necessary. 5.4.9 Bluff Erosion and Setbacks As previously indicated, the established string lines for structures and associated improvements at the subject site are considered appropriate and the site is not anticipated to be significantly impacted by the widespread coastal bluff erosion that typically results in relatively fast-paced coastline collapse and/or recession in other areas of San Diego County. Nevertheless, erosion of all coastal areas and shoreline retreat is inevitable, especially over extended periods of time. Based on the information provided above, as well as our understanding that the proposed improvements are planned to be landward (east) of the established string lines, it is our opinion that proposed building improvements need not be excessively setback from the existing "top of bluff' location. However, foundations shall have adequate setback/embedment as recommended in the subsequent sections of this report for geotechnical engineering purposes. 6.0 CONCLUSIONS AND RECOMMENDATIONS 6.1 General We conclude that the proposed construction on the site is feasible from a geotechnical standpoint, provided the recommendations in this report are incorporated into the design and construction of the project. \\Cte..servcr\projects\ I 0-8001 to 10-9000 Projects\l 0-8790G\Rpt_Geotech .doc Preliminary Geotechnical Investigation Page 14 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 CTE Job No. 10-8790G Based on our subsurface investigation and engineering analysis, the proposed improvements can be supported on typical spread foundations designed and constructed as recommended herein. However, minor preparatory site grading may be required. Specific recommendations for the design and construction of improvements at the subject site are included in the subsequent sections of this report. 6.2 Site Preparation 6.2.1 General The site should be cleared of any debris and other deleterious materials. In areas to receive engineered fill, structures or distress-sensitive improvements, expansive, surficial eroded, desiccated, burrowed, or otherwise loose or disturbed soils should be removed to the depth of competent native material and to a minimum 12 inches below the proposed rough building pad elevation, whichever is deeper. Based on our onsite explorations, we anticipate uniform removals of 12 inches below the proposed rough building pad elevation for the building footprint will generally be adequate. However, localized areas of deeper removals may be required. In addition, any materials disturbed during demolition of existing site improvements shall be completely removed and replaced as engineered fill. Organic and other deleterious materials not suitable for structural backfill should be disposed of offsite at a legal disposal site. CTE should review the project grading and foundation plans as they become more complete. Prior to placing any engineered fill, exposed subgrade shall be scarified (as necessary), moisture conditioned to near optimum moisture content, and properly recompacted. \\Cte_servcr\projects\I 0-800 I to 10-9000 Projects\I 0-87900\Rpt_Gcotech.doc Preliminary Geotechnical Investigation Page 15 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 CTE Job No. 10-8790G General engineered fill shall be compacted to a minimum 90% relative compaction (per ASTM D 1557) at the near optimum moisture contents. 6.2.2 Site Excavations Site excavations can generally be accomplished using heavy-duty construction equipment. Design recommendations for temporary construction slopes are provided in a subsequent section of this report. Site excavations should be observed by CTE. Such observations are essential to identify field conditions that differ from those identified during our subsurface investigation and to adjust designs to actual field conditions encountered. 6.2.3 Fill Placement and Compaction As stated, an engineer or geologist from CTE should be called upon to verify that the proper site preparation has occurred before fill placement begins. As stated, following the recommended removals, areas to receive fills or improvements should be scarified, moisture conditioned near optimum moisture content, and properly recompacted. General fill and backfill should be compacted to a minimum relative compaction of 90% as evaluated by ASTM D-1557 (except in pavement areas) at moisture contents near optimum (generally within two percent). The optimum lift thickness for backfill soil will be dependent on the type of compaction equipment used. Generally, backfill should be placed in uniform lifts not exceeding eight inches in loose thickness. If proposed, sloping backfill shall be properly keyed and benched. Backfill placement and compaction should be done in overall conformance with geotechnical recommendations and local VCtc_ser'er\projcctsI 0.8001 to 10-9000 Projects\I 0-87900\Rpt_Geoiech.doc Preliminary Geotechnical Investigation Page 16 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 CTE Job No. 10-8790G ordinances. All grading shall be performed in accordance with the regulations of the governing authorities. 6.2.4 Fill Materials Soils derived from on-site materials are considered suitable for reuse on the site as fill, provided they are screened of significant organic materials and materials greater than three inches in maximum dimension, if encountered. Imported fill beneath structures, pavements and walks should have an expansion index less than or equal to 30 (per UBC 18-I-B) with less than 35% passing the no. 200 sieve. Imported fill soils for use in structural or slope areas should be evaluated by the soils engineer to determine strength characteristics before placement on the site. 6.3 Temporary Construction Slopes Sloping recommendations for unshored temporary excavations are provided herein. The recommended slopes should be relatively stable against deep-seated failure, but may experience localized sloughing. Recommended slope ratios are set forth in Table 3. TABLE 3 TEMPORARY SLOPE RATIOS SOILS TYPE I SLOPE RATIO I MAXIMUM HEIGHT B (Quaternary Terrace Deposits) I 1:1 (MAXIMUM) I 10 FEET Actual field conditions and soil type designations must be verified by a "competent person" while excavations exist according to Cal-OSHA regulations. In addition, the above sloping recommendations do not allow for potential water seepage, or surcharge loading at the top of \\Cte_servcr\projects\l 0.8001 to 10-9000 Projects\l 0-8790G\Rpt_Geotcch.doc Preliminary Geotechnical Investigation Page 17 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 CTE Job No. 10-8790G slopes by vehicular traffic, equipment or materials. Appropriate surcharge setbacks must be maintained from the top of all unshored slopes. Excavations shall not encroach within a 1:1 plane extended down from adjacent structures to remain. 6.4 Foundations and Slab Recommendations 6.4.1 General The following recommendations are for preliminary planning purposes only. These foundation recommendations should be reviewed after completion of earthwork and testing of surface soils. We anticipate all foundations for proposed structures will be founded upon competent native materials. Foundations should not straddle transitional conditions (changes from cut to fill soils). As a result, localized footings may require deepening to reach competent native materials. 6.4.2 Spread Foundations, Soldier Beams and Slabs-on-Grade Continuous and isolated spread footings are suitable for use at this site. We anticipate that all building footings (deepened as/if necessary) will be founded entirely upon competent native materials. Foundation dimensions and reinforcement should be based on allowable bearing values of 2,000 pounds per square foot (psO for footings embedded a minimum of 18 inches below the lowest adjacent rough grade elevation and bearing upon competent native materials. The allowable bearing value may be increased by one third for short duration loading which includes the effects of wind or seismic forces. \\Ctc_scrvciprojects\I 0-800 I to 10-9000 ProjecIsI 0-8790G\Rpt_Gcotech .doc Preliminary Geotechnical Investigation Page 18 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 CTE Job No. 10-8790G Minimum footing reinforcement for continuous footings should consist of four No. 5 reinforcing bars; two placed near the top and two placed near the bottom or as per the project structural engineer. The structural engineer should design isolated footing reinforcement. It is recommended that isolated footings be connected to each other or adjacent continuous foundations via minimum 12-inch by 12-inch tie beams with minimum reinforcing steel percentages. As a precautionary measure, it is generally recommended that all foundations attain a minimum 12-foot horizontal distance to daylight. Deepening of locally affected foundations may be a suitable means of attaining the prescribed foundation setbacks. For conventional soldier beam and lagging shoring systems, soldier beams, spaced at least three diameters on center, may be designed using an allowable passive pressure of 350 psf per foot of depth, up to a maximum of 3,500 psf, for the portion of the soldier beam embedded in competent native materials. Provisions should be made for firm contact between the beam and the surrounding soils. Concrete placed in soldier beams below the proposed excavation should have adequate strength to transfer the imposed pressures. A lean concrete mix may be used in the soldier pile above the base of the proposed excavation. Soldier beam installations should be observed by CTE. Due to the locally erodible nature of onsite materials, continuous timber lagging between soldier beams is recommended. Lagging should be designed for the recommended earth \\Cte_server\projccts\10-8001 to 10-9000 Projects\I 0-87900\Rpt_Geotech.doc Preliminary Geotechnical Investigation Page 19 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 CTE Job No. 10-8790G pressures but be limited to a maximum pressure of 450 psf due to arching in the soils. Voids created behind lagging by sloughing of locally cohesionless soil layers should be grouted or slurry filled, as necessary. In addition, generally the upper two to four feet of lagging should be grouted or slurry-filled to assist in diverting surface water from migrating behind the shoring walls. Lightly loaded concrete slabs should be a minimum of five inches thick. Minimum slab reinforcement should consist of #4 reinforcing bars placed on 18-inch centers, each way, at mid-slab height. Moisture sensitive floor areas shall be underlain by a minimum 10- mil visqueen layer, with all laps sealed or taped. A two-inch thick layer of clean sand may be placed upon the visqueen material for protection during steel and concrete placement. Slabs subjected to heavier loads may require thicker slab sections and/or increased reinforcement. 6.4.3 Foundation Settlement Based on the preliminary plans as well as the conditions observed at the site, the maximum total static settlement is expected to be less than 1.0 inches and the maximum differential static settlement is expected to be less than 0.5 inches. Total and differential dynamic settlements are anticipated to be less than 0.5 inches. 6.5 Lateral Resistance and Earth Pressures Foundations placed in competent native materials may be designed using a coefficient of friction of 0.30 (total frictional resistance equals the coefficient of friction times the dead load). A design passive resistance value of 250 pounds per square foot per foot of depth (with a maximum \\Cte_scrver\projccts\10-8001 to 10-9000 ProjcctsI 0-8790G\Rpt_Gcotech .doc Preliminary Geotechnical Investigation Page 20 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 CTE Job No. 10-8790G value of 1,000 pounds per square foot) may be used. The allowable lateral resistance can be taken as the sum of the frictional resistance and the passive resistance, provided the passive resistance does not exceed two-thirds of the total allowable resistance. Walls and permanent shoring below grade up to 12 feet high and backfilled with or installed in granular soils may be designed using the equivalent fluid weights given in Table 4 below. If segmental block walls are proposed at the site, our office shall be contacted and additional design and construction recommendations will be provided upon request. TABLE 4 EQUIVALENT FLUID UNIT WEIGHTS (pounds per cubic foot) WALL TYPE LEVEL BACKFILL SLOPE BACKFILL 2:1 (HORIZONTAL: VERTICAL) CANTILEVER WALL 35 55 (YIELDING) r____ RESTRAINED WALL 55 85 The above values assume non-expansive backfill and free draining conditions. Measures should be taken to prevent a moisture buildup behind all walls below grade. Drainage measures should include free draining backfill materials and perforated drains. Drains should discharge to an appropriate offsite location. We recommend that walls below grade be backfihled with soils having an expansion index of 20 or less. The backfill area should include the zone defined by a 1:1 sloping plane, extended back from the base of the wall. Wall backfill should be compacted to at least 90 percent relative compaction, based on ASTM D1557-91. Backfill should not be placed until walls have achieved \\Cte_scrver\projectsI 0-800 I to 10-9000 Projccts\I O-87900\Rpt_Gcotcch.doc Preliminary Geotechnical Investigation Page 21 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 CTE Job No. 10-8790G adequate structural strength. Heavy compactors, which could cause distress to walls, should not be used. 6.6 Exterior Flatwork To reduce the potential for distress to exterior flatwork caused by minor settlement of foundation soils, we recommend that such flatwork be reinforced and installed with crack-control joints at appropriate spacing as designed by the project architect. The upper 12 inches of subgrade should be properly recompacted before placing concrete. Flatwork should be a minimum four inches thick. We recommend flatwork be reinforced with minimum #3 rebar spaced at 18 inches, on center, both ways. Reinforcing should be located near mid-height of the concrete section. 6.7 Vehicular Pavements The proposed development may include the construction of pavement areas. Presented in Table 5 below are recommended pavement sections. Two options are presented. Option 1 is for construction of asphalted concrete pavements; Option 2 is for construction of full-depth concrete pavements. The pavement sections presented are based on estimated traffic indices and the design value for the Resistance "R"- Value of onsite materials. The upper 12 inches of subgrade and all base materials shall be compacted to 95% of laboratory determined maximum dry density, as per ASTM D1557, at moisture contents near optimum. \Cte_scrvcrprojects\I 0-8001 to 10-9000 Projccts\I O-8790G\Rpt_Gcotcch.doc Preliminary Geotechnical Investigation Page 22 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 CTE Job No. 10-8790G TABLE5 PRELIMINARY RECOMMENDED PAVEMENT THICKNESS Option I: Option 2: Preliminary Asphalt Pavements Full Traffic Area Assumed Traffic Subgrade Depth AC Class II Index "R"-Value Thickness Aggregate Base Concrete (inches) Thickness Pavements (inches) (inches) Drive and 4.5 25+ 2.5 4.0 5.5 Parking Areas or or 4.0 0.0 At the owner's option, upon completion of preparatory grading in the proposed pavement areas, additional subgrade sampling and testing for "R" Value determination can be conducted. This additional testing will enable us to modify the pavement sections based on the as-graded conditions, if necessary. 6.8 Drainage Surface runoff should be collected and directed away from improvements by means of appropriate erosion reducing devices and positive drainage should be established around the proposed improvements.. Positive drainage should be directed away from improvements at a gradient of at least two percent for a distance of at least five feet. Surficial contours within the area should keep water from affecting the foundations provided planter areas are not over watered. The project civil engineer should evaluate the on-site drainage and make necessary provisions to keep surface water from affecting the site. \\Cte_servcr\projcc1sI 0-8001 to 10-9000 Projccts\I O-8790G\Rpt_Geotech .doc Preliminary Geotechnical Investigation Page 23 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 CTE Job No. 10-8790G 6.9 Slopes Constructed slopes should be inclined at 2:1 (horizontal: vertical) or flatter. Although graded slopes on this site will be grossly stable (i.e., factor of safety greater than 1.5), the soils will be somewhat erodible. Therefore, runoff water should not be permitted to drain over the edges of slopes unless that water is confined to properly designed and constructed drainage facilities. Erosion resistant vegetation should be maintained on the face of all slopes. All proposed slopes should be properly keyed and benched. Typically, soils along the top portion of a fill slope face will tend to creep laterally. We do not recommend that distress sensitive landscape improvements be constructed within five feet of slope crests in fill areas. 6.10 Construction Observation The recommendations provided in this report are based on preliminary design information for the proposed construction and the subsurface conditions found in the explorations. The interpolated subsurface conditions should be checked in the field during construction to verify that conditions are as anticipated. Recommendations provided in this report are based on the understanding and assumption that CTE will provide the observation and testing services for the project. All earthwork should be observed and tested to verify that grading activity has been performed according to the recommendations contained within this report. All foundation excavations shall be evaluated by the project engineer before reinforcing steel placement. \\Cte_serv&projccts\I 0-8001 to 10.9000 ProjectsI 0.87900\Rpt_Gcotech.doc Preliminary Geotechnical Investigation Page 24 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 CTE Job No. 10-8790G 6.11 Plan Review CTE should review all project grading and foundation plans before the start of earthworks to identify potential conflicts with the recommendations contained in this report. 7.0 LIMITATIONS OF INVESTIGATION The recommendations provided in this report are based on the anticipated construction and the subsurface conditions found in our explorations. The interpolated subsurface conditions should be checked in the field during construction to verify that conditions are as anticipated. Recommendations provided in this report are based on the understanding and assumption that CTE will provide the observation and testing services for the project. All earthworks should be observed and tested to verify that grading activity has been performed according to the recommendations contained within this report. The project engineer should evaluate all footing trenches before reinforcing steel placement. The field evaluation, laboratory testing and geotechnical analysis presented in this report have been conducted according to current engineering practice and the standard of care exercised by reputable geotechnical consultants performing similar tasks in this area. No other warranty, expressed or implied, is made regarding the conclusions, recommendations and opinions expressed in this report. Variations may exist and conditions not observed or described in this report may be encountered during construction. \Ctc_serv&.projccts\I 0-8001 to 10-9000 Projccts\I 0-8790G\RpI_Gcotech.doc Preliminary Geotechnical Investigation Page 25 Proposed Improvements to Ocean Street Property 3053 Ocean Street, Carlsbad, California December 27, 2007 CTE Job No. 10-8790G Our conclusions and recommendations are based on an analysis of the observed conditions. If conditions different from those described in this report are encountered, our office should be notified .and additional recommendations, if required, will be provided upon request. We appreciate this opportunity to be of service on this project. If you have any questions regarding this report, please do not hesitate to contact the undersigned. Respectfully submitted, CONSTRUCTION TESTING & ENGINEERING, INC. Math, GE T. Principal Engineer Un No. 2665 Urn l Exp. 12131108 J5J )rtin E Siem, CEG #2311 C_$enior Engineering Geologist LYNCH No. 1890 CERTFUZD ENGINEERN3 GEOLOGSTA \\Cte_scrver\projects\ 10-8001 to 10-9000 Projects\I 0-8790G\Rpt.Geotech.dOC u p CyV H; H> APPROXIMATE 'c SITE LOCATION J O[J in [ 2.ioo 4t cl Carlsbad cD Aqua -c ZL r1p:ata N AN'Q A CONSTRUCTION TESTING & ENGINEERING, INC. GFOTECHNCAL AND CONSTRUCTION ENGINEERING TESTING AND INSPECTION ç 1441 EIONTIFI ROAD STE 115 ESCONDIDO CA 52026 (7614, 746-4555 OlE JOB NO. SITE INDEX MAP 10-8790G PROP()EI) RESIIHNIJAI. STRUCTURE SCALE AS SHOWN APN: 203-2 1-06-010 OCEAN STREET EARl SBAI), (ALII'ORNIA DATE FIGURE 1 APPENDIX A REFERENCES CITED \Ctc_scrver\projects\I 0-8001 to 10-9000 Projccts\I 0-8790GRpt_Geotech .doc REFERENCES CITED Blake, T.F., 1996, "EQFAULT," Version 2.20, Thomas F. Blake Computer Services and Software California Building Code, 2001, California Code of Regulations, Title 24, Part 2, Volume 211art, Earl W. and Bryant, W.A., 1997, "Fault-Rupture Hazard Zones in California, Aiquist-Priolo Earthquake Fault Zoning Act with Index to Earthquake Fault Zones Maps," California Division of Mines and Geology, Special Publication 42. Cao, T.; Bryant, W. A; Rowshandel, B.; Branum, D.; and Wills, C. J. June 2003: The Revised 2002 California Probabilistic Seismic Hazard Maps. FEMA Flood Hazard Mapping, (n.d.). Retrieved March, 2006 from http://www.fema.gov/ffimlen main.shtm Jennings, C. W., 1987, "Fault Map of California with Locations of Volcanoes, Thermal Springs and Thermal Wells." Tan, S. S., and Giffen, D.G., 1995, "Landslide Hazards in the Northern Part of the San Diego Metropolitan Area, San Diego County, California: Landslide Hazard Identification Map", California Department of Conservation, Division of Mines and Geology, Open- File Report 95-04, State of California, Division of Mines and Geology, Sacramento, California. LiquifyPro, Version 4, Civiltech Corporation, 2003, "Computer Program for Evaluation of Liquefaction Potential and Calculations of Settlement of Soil Deposits Due to Seismic Loads per NCEER Workshop and SP1 17 Implementation." McCulloch, D.S., 1985, "Evaluating Tsunami Potential" in Ziony, J.I., ed., Evaluation Earthquake Hazards in Los Angeles Region - An Earth-Science Perspective, U.S. Geological Survey Professional Paper 1360 Tan, S. S., and Kennedy M., 1996, "Geological Map of the Oceanside and San Marcos 7.5' Quadrangles", Geological Maps of the Northwestern Part of San Diego County, California, California Department of Conservation, Division of Mines and Geology. Uniform Building Code, 1997, Maps of Known Active Fault Near-Source Zones in California and Adjacent Portions of Nevada. \Cte_servcr\projects\I 0-8001 to 10.9000 Projectsl 0-8790G\Rpt_Geotech.doc APPENDIX B EXPLORATION LOGS Ctc_server\projccts\I 0-8001 to 10-9000 Projccts\I 0-8790GRpt_Gcotcch.doc ' CONSTRUCTION TESTING & ENGINEERING, INC. GFoTCchNIcAt I CON5IUC1ION (NINtIRuIlG TESAIPIC AND INSPECTION tin MOVIEL fioO. SouTh us I hSCOohISO. Cu foIl I ;11.141 4055 DEFINITION OF TERMS PRIMARY DIVISIONS SYMBOLS SECONDARY DIVISIONS GRAVELS CLEAN ' " WELL GRADED GRAVELS, GRAVEL-SAND MIXTURES MORE THAN GRAVELS • LITTLE OR NO FINES !.. GP "tr POORLY GRADED GRAVELS OR GRAVEL SAND MIXTURES, Z HALF OF <5% FINES ARSE LITTLE OF NO FINES ________ GRAVELS GM SILTY GRAVELS, GRAVEL-SAND-SILT MIXTURES, NON-PLASTIC FINES 3 o u N FRACTION IS X LARGER THAN NO.4 SIEVE WITH FINES GC CLAYEY GRAVELS, GRAVEL-SAND-CLAY MIXTURES, PLASTIC FINES SANDS CLEAN : r- WELL GRADED SANDS, GRAVELLY SANDS, LITTLE OR NO Ln E - a d MORE THAN HALF OF SANDS -- _________-_ FINES __________________________________________ . POORLY GRADED SANDS, GRAVELLY SANDS, LITTLE OR COARSE <5% FINES NO FINES SANDS SILTY SANDS, SAND-SILT MIXTURES, NON-PLASTIC FINES V FRACTION IS SMALLER THAN WITH FINES CLAYEY SANDS, SAND-CLAY MIXTURES, PLASTIC FINES NO.4 SIEVE INORGANIC SILTS, VERY FINE SANDS, ROCK FLOUR, SILTY Cz u u.s SILTS AND CLAYS JJ OR CLAYEY FINE SANDS. SLIGHTLY PLASTIC CLAYEY SILTS pzzx. ML o LIQUID LIMIT IS INORGANIC CLAYS OF LOW TO MEDIUM PLASTICITY, LESSTHAN5O GRAVELLY, SANDY, SILTS OR LEAN CLAYS ORGANIC CLAYS OF LOW PLASTICITY ORGANIC SILTS AND z En r, ZZo . o. r'r'o zz", INORGANIC SILTS, MICACEOUS OR DIATOMACEOUS FINE —< _Jo rX SILTS AND CLAYS MH SANDY OR SILTY SOILS, ELASTIC SILTS INORGANIC CLAYS OF HIGH PLASTICITY. FAT CLAYS LIQUID LIMIT IS GREATER THAN 50 ORGANIC CLAYS OF MEDIUM TO HIGH PLASTICITY. ORGANIC SILTY CLAYS HIGHLY ORGANIC SOILS PT PEAT AND OTHER HIGHLY ORGANIC SOILS GRAIN SIZES BOULDERS COBBLES GRAVEL I SAND SILTS SILTS AND CLAYS COARSE I FINE I COARSE I MEDIUM I FINE 12" 3" 3/4" 4 10 40 200 CLEAR SQUARE SIEVE OPENING U.S. STANDARD SIEVE SIZE ADDITIONAL TESTS (OTHER THAN TEST PIT AND BORING LOG COLUMN HEADINGS) MAX- Maximum Dry Density PM- Permeability PP- Pocket Penetrometer GS- Grain Size Distribution SG- Specific Gravity WA- Wash Analysis SE- Sand Equivalent HA- Hydrometer Analysis DS- Direct Shear El- Expansion Index AL- Atterberg Limits UC- Unconfined Compression CHM- Sulfate and Chloride RV- R-Value MD- Moisture/Density Content , pH, Resistivity CN- Consolidation M- Moisture COR - Corrosivity CP- Collapse Potential SC- Swell Compression SD- Sample Disturbed HC- Hydrocollapse 01- Organic Impurities REM- Remolded FIGURE:I BLI A ' CONSTRUCTION TESTING & ENGINEERING, INC. GLOIECIINICAL I CONSTRUCTION ENGINEERING TINTING AND INSPECTION tin uiiuit Ro*o. Sill! 115 I £scaNDuoo, ci isis. i SL- PROJECT: DRILLER: SHEET: of CTE JOB NO: DRILL METHOD: DRILLING DATE: LOGGED BY: SAMPLE METHOD: ELEVATION: — I BORING LEGEND Laboratory Tests ' Ili .2 0 DESCRIPTION Block or Chunk Sample - - - - Bulk Sample -5- - - - - - - Standard Penetration Test 10- - - / - - Modified Split-Barrel Drive Sampler (Cal Sampler) - - - - I - - Thin Walled Army Corp. of Engineers Sample - - - 1 5- - - - Groundwater Table - - - - - - Soil Type or Classification Change 20- - Formation Change [(Approximate boundaries queried (?)1 - "SM Quotes are placed around classifications where the soils exist in situ as bedrock 25 — — — — — — — FIGURE: I BL2 CONSTRUCTION TESTING & ENGINEERING, INC. 055ICCHNICAL I CONSTRUCTION LNGII451RUIC TITlING AND INSPECTION MONIICI ROAD. SOIlS Ill I I3COUOIDI. CA 07011 I 100.I4I.4155 PROJECT: Ocean Street DRILLER: Pac Drilling SHEET: I of 2 CTE JOB NO: I0-8790G DRILL METHOD: Tripod '/6" Solid Flight Auger DRILLING DATE: 2/14/2007 LOGGED BY: DK SAMPLE METHOD: Bulk, Cal, SPT ELEVATION: 44' cn ! BORING: B-i Laboratory Tests I Eli I I CL DESCRIPTION -0- - - - ____ - - TOPSOIL; - 0': Moist, dark brown, silty sand wi organics and cobbles. OUATERNARY TERRACE DEPOSITS (Ot'): SE, CHEM - SM .5': Slightly moist, brown silty fine SAND (SM). • A 3 SM-SP ------------------------------------------------------ 3': Medium dense, slightly moist, brown to orange brown, silty MD ' 5 fine grained SAND (SM) to poorly graded SAND (SP) with silt. 8 4 SP-SM 5': Medium dense, slightly moist, brown to orange brown silty WA 4 SAND (SM) to poorly graded SAND (SP-SM) with silt. 6 10- SP-SM 10': Medium dense, slightly moist, brown to orange brown silty WA 4 SAND (SM) to poorly graded SAND (SP-SM) with silt. 6 1 9 SP-SM 15': Dense, slightly moist, light brown to tan fine to medium poorly I 10 graded SAND (SP-SM) with silt. J 10 20 12 WA - - 14 B-I TESTING & ENGINEERING, INC. 9*9 CONSTRUCTION 050ICCI4NICAt I CONSTRUCTIOSI Eucsu114isc TOSSING ASS INSPICISON 1441 MINIM ROSS. 45111 115 I ISCSNOIOO, CA 11115 I ISL1l5.C155 PROJECT: Ocean Street DRILLER: Pac Drilling SHEET: 2 of 2 CTE JOB NO: I0-8790G DRILL METHOD: Tripod w/6" Solid Flight Auger DRILLING DATE: 2II4I2007 LOGGED BY: DK SAMPLE METHOD: Bulk, Cal, SPT ELEVATION: 44' .5 ' .! BORING: B-i Laboratory Tests - ' . . DESCRIPTION — — Continue - 10 SW-SM light brown to brown, fine to Dense, slightly moist, medium - 26 poorly graded SAND (SW-SM) with silt. - - 22 SP/SM Becomes pale gray, fine grained SAND (SP) to silty SAND (SM). - SP-SM Dense, slightly moist, brown fine to medium poorly graded SAND ($F:SM'L?lith.siLt.................................... 3 ID SP-SM Dense, moist to wet, pale gray, fine to coarse SAND with silt. - 16 (SP-SM) and trace gravel. 19 - Total depth 31.5' fbg. - Groundwater at 3 1'. Backfilled with cuttings and bentonite chips. — — — — — — — — I B-I L 1 '. CONSTRUCTION TESTING & ENGINEERING, INC. GCOA(CHNICAL CONIIAUCTION EUCINIIAsUC Ttsiuwc AO I,ls,CCtuOU ¶;1- _________________________ 1441 UOII(t ROAD. SUITE 115 I ISCONAISO. CU 51076 1 161.141.4153 PROJECT: Ocean Street DRILLER: Pac Drilling SHEET: I of 2 CTE JOB NO: I0-8790G DRILL METHOD: Tripod w/6" Solid Flight Auger DRILLING DATE: 2/1412007 LOGGED BY: DK SAMPLE METHOD: Bulk, Cal, SPT ELEVATION: 33 — - — 1.2 U .3 E ' ' ! BORING: B-2 Laboratory Tests U. C U. C B ' :' ö ' DESCRIPTION - - - - TOPSOIL/FILL: Moist, brown, silty fine grained SAND (SM) - with organics. - QUATERNARY TERRACE DEPOSITS (Qt); - 8 SP-SM 5': Medium dense, slightly moist, orange brown to brown fine MAX, SE ( 8 to medium poorly graded SAND (SP-SM) with silt. MD, CN - 10 -10- 1 3 sp 10': Medium dense, slightly moist, light gray brown to tan fine to WA - I 5 medium SAND (SP) with trace silt and coarse sand. 15 18 SP 15': Dense, slightly moist, light brown to tan fine to medium poorly CN / 19 graded SAND (SP) with some coarse sand grains. 31 20- 12 SP 20': Dense, moist to wet, light brown, fine to coarse SAND with 12 silt (SP). 15 -25- — - — — — B-2 A I \ CONSTRUCTION TESTING & ENGINEERING, INC. O(oI(CHIIICAL I CONDflUCTtOU ENCIuIIRIN TtStuu AND INSPECTION ¶L- _________________________ 1411 MOAIICI ROAD. 54111 III I ISCOI101OD. CA DDOIA I ?6I.711.415S PROJECT: Ocean Street DRILLER: Pac Drilling SHEET: 2 of 2 CTE JOB NO: 10-8790G DRILL METHOD: Tripod w/6 Solid Flight Auger DRILLING DATE: 2/14/2007 LOGGED BY: DK SAMPLE METHOD: Bulk, Cal, SPT ELEVATION: 31' - - - CL CL -.. .3 ' !° BORING: B-2 Laboratory Tests 5 . CL ej 75 DESCRIPTION :1 20 1 iP 25': Very dense, moist to wet, gray brown, fine to coarse silty - F• J 40 SAND with gravels (SM-SP. WA - Total depth 26' fbg. - Groundwater at 20'. - - Backfilled with bentonite chips and cuttings. B-2 APPENDIX C LABORATORY METHODS AND RESULTS \\Cte_serveiiprojecls\I 0.8001 to 10-9000 Projects\I 0-8790G\Rpt_Gcotech .doc APPENDIX C LABORATORY METHODS AND RESULTS Laboratory tests were performed on representative soil samples to detect their relative engineering properties. Tests were performed following test methods of the American Society for Testing Materials or other accepted standards. The following presents a brief description of the various test methods used. Laboratory results are presented in the following section of this Appendix. Classification Soils were classified visually according to the Unified Soil Classification System. Visual classifications were supplemented by laboratory testing of selected samples according to ASTM D2487. Particle-Size Analysis Particle-size analyses were performed on selected representative samples according to ASTM D422. In-Place Moisture/Density The in-place moisture content and dry unit weight of selected samples were determined using relatively undisturbed chunk soil samples. Modified Proctor Laboratory maximum dry density and optimum moisture content were performed according to ASTM D1557, Method A. A mechanically operated rammer was used during the compaction process. Sand Equivalent Laboratory determinations of the sand equivalent for soils were performed according to ASTM D2419. Chemical Analysis Soil materials were collected with sterile sampling equipment and tested for Sulfate and Chloride content, pH, Corrosivity, and Resistivity. Consolidation To assess their compressibility and volume change behavior when loaded and wetted, relatively undisturbed samples of representative samples from the investigation were subject to consolidation tests (ASTM D2435). \\Cte_server\projects\I 0-8001 to 10-90W Projects\I 0-8790GRpt_Geotech.doc CONSTRUCTION TESTING & ENGINEERING, INC. GIOICCHNICAL I CO,1SUC1tO ENGIIUIl T15T1MC MJO IU5PlCtIO 9~*K 1441 M041111 R.*O. Sulli I IS I (StO5IOO. co 41015 I I6I.I46.I4 15 200 WASH ANALYSIS LOCATION DEPTH PERCENT PASSING CLASSIFICATION (feet) #200 SIEVE B-I 3.0 14.6 SM B-I 10.0 7.6 SP-SM B-I 20 5.3 SP=SM B-2 10.0 4.2 SP 8-2 25 5.6 SP=SM SULFATE LOCATION DEPTH RESULTS (feet) ppm B-I 6.0 48.8 CHLORIDE LOCATION DEPTH RESULTS (feet) ppm B-I 6.0 24.5 CONDUCTIVITY CALIFORNIA TEST 424 LOCATION DEPTH RESULTS (feet) us/cm B-I 6.0 58.1 RESISTIVITY CALIFORNIA TEST 424 LOCATION DEPTH RESULTS (feet) ohms/cm B-I 6.0 15300 MAXIMUM DRY DENSITY & OPTIMUM MOISTURE CONTENT (MODIFIED PROCTOR) LOCATION DEPTH OPTIMUM MOISTURE DRY DENSITY (feet) (%) (pci) HB-2 0-4 10.1 114.6 IN-PLACE MOISTURE AND DENSITY LOCATION DEPTH MOISTURE DRY DENSITY (feet) (%) (pci) B-I 3 II 110.3 B-2 5 7.3 105.7 B-2 15 3.8 104.4 LABORATORY SUMMARY CTE JOB NO. 10-87900 0.00% 1.00% 2.00% 3.00% 4.00% 5.00% 6.00% 7.00% 8.00% Z 9.00% 0 U) U) 10.00% 0. 3 11.00% 12.00% 13.00% 14.00% 15.00% 16.00% 17.00% 18.00% 19.00% 20.00% Immmmmlli mmmmli IME0011111MMEN11111 I MWEEMEN 1000 10000 100000 VERTICAL EFFECTIVE STRESS (psf) SWELLJCOMPRESSION TEST Sample Designation Depth (ft) Symbol Legend FIELD MOISTURE B-2 15 SAMPLE SATURATED - REBOUND Initial Moisture (%): 3.8 Initial Dry Density (pcf): 104.4 CTE JOB NO: 10-8790G Final Moisture (%): 20.4 Final Dry Denstiy (pcf: 112.3 FIGURE NO.: A 0.00% 1.00% 2.00% 3.00% 4.00% 5.00% 6.00% 7.00% - — — — - III!' ________uAhII. MENEM 111111 8.00% 9.00% 0 111111 hull I.1II, 1jul11 111111 111111 111111 111111 111111 111111 111111 1,1111 T4 ;iI I4..iik I SWELL/COMPRESSION TEST FIELD MOISTURE B-2 5 SAMPLE SATURATED -REBOUND Initial Moisture (%): 7.3 Initial Dry Density (pcf): 105.7 CTE JOB NO: 10-8790G Final Moisture (%): 24.7 Final Dry Denstiy (pcO: 111.5 FIGURE NO.: B U U ii 11 II 145 140 135 130 125 C' 120 110 ce In 105 100 95 90 85 0 5 10 15 20 25 30 35 PERCENT MOISTURE (%) ASTM D1557 METHOD A B 0 C MODIFIED PROCTOR RESULTS I MAXIMUM I OPTIMUM LAB I SAMPLE DEPTH I SOIL DESCRIPTION I DRY DENSITY I MOISTURE NUMBER NUMBER I (FEET) I I (PCF) I CONTENT (%) 17824 I B-2 1-5 Silty Sand 121.0 12.0 CTE JOB NO: I A CONSTRUCTION TESTING & ENGINEERING, INC. DATE: 12/07 10-8790G %L••• GEOTECHNICAI. AND CONSTRUCTION ENGINEERING TESTING AND INSPECTION 1441 MONTIEL ROAD. STE 115 ESCONDIDO CA. 92026 FIGURE: C CONSTRUCTION TESTING & ENGINEERING, INC, GEOTECHNICAL AND CONSTRUCTION ENGINEERING TESTING AND INSPECTION 2414 VINEYARD AVENUE ESCONDIDO, CA 92029 (760) 746-4955 FAX (760) 746-9806 ENGINEERING, INC. SAND EQUIVALENT FORM DATE: 2-21-07 LAB #: 17066 JOB #: 10-8790G JOB NAME: OCEAN STREET SAMPLE LOCATION: B-i © 1'— 6' SAND EQUIVALENT #2 SAND 2.5 CLAY 5.2 SAND EQUIVALENT 148 AVERAGE: 48 LAB TECH: Anthony Scott DATE: 2-21-07 ASTM D-2419 GEOTECHNICAL & CONSTRUCTION ENGINEERING TESTING & INSPECTION 2414 VINEYARD AVENUE ESCONDIDO, CA 92029 (760) 746-4955 FAX (760) 746-9806 CONSTRUCTION TESTING & ENGIN EERING,,INC, GEOTECHNICAL AND CONSTRUCTION ENGINEERING TESTING AND INSPECTION 2414 VINEYARD AVENUE ESCONDIDO, CA 92029 (760) 746-4955 FAX (760) 746-9806 ENGINEERING, INC. SAND EQUIVALENT FORM DATE: 2-21-07 LAB #: 17066 JOB #: 10-8790G JOB NAME: OCEAN STREET SAMPLE LOCATION: B-2 © l'— 5' SAND EQUIVALENT #1 #2 SAND 2.5 CLAY 6.0 SAND EQUIVALENT 42 AVERAGE: 42 LAB TECH: Anthony Scott DATE: 2-21-07 ASTM D-2419 GEOTECHNICAL & CONSTRUCTION ENGINEERING TESTING & INSPECTION 2414 VINEYARD AVENUE ESCONDIDO, CA 92029 (760) 746-4955 FAX (760) 746-9806 APPENDIX D STANDARD SPECIFICATIONS FOR GRADING Appendix D Page D-1 Standard Specifications for Grading Section 1 - General Construction Testing & Engineering, Inc. presents the following standard recommendations for grading and other associated operations on construction projects. These guidelines should be considered a portion of the project specifications. Recommendations contained in the body of the previously presented soils report shall supersede the recommendations and or requirements as specified herein. The project geotechnical consultant shall interpret disputes arising out of interpretation of the recommendations contained in the soils report or specifications contained herein. Section 2 - Responsibilities of Project Personnel The geotechnical consultant should provide observation and testing services sufficient to general conformance with project specifications and standard grading practices. The geotechnical consultant should report any deviations to the client or his authorized representative. The Client should be chiefly responsible for all aspects of the project. He or his authorized representative has the responsibility of reviewing the findings and recommendations of the geotechnical consultant. He shall authorize or cause to have authorized the Contractor and/or other consultants to perform work and/or provide services. During grading the Client or his authorized representative should remain on-site or should remain reasonably accessible to all concerned parties in order to make decisions necessary to maintain the flow of the project. The Contractor is responsible for the safety of the project and satisfactory completion of all grading and other associated operations on construction projects, including, but not limited to, earth work in accordance with the project plans, specifications and controlling agency requirements. Section 3 - Preconstruction Meeting A preconstruction site meeting should be arranged by the owner and/or client and should include the grading contractor, design engineer, geotechnical consultant, owner's representative and representatives of the appropriate governing authorities. Section 4 - Site Preparation The client or contractor should obtain the required approvals from the controlling authorities for the project prior, during and/or after demolition, site preparation and removals, etc. The appropriate approvals should be obtained prior to proceeding with grading operations. STANDARD SPECIFICATIONS OF GRADING Page 1 of 24 Appendix D Page D-2 Standard Specifications for Grading Clearing and grubbing should consist of the removal of vegetation such as brush, grass, woods, stumps, trees, root of trees and otherwise deleterious natural materials from the areas to be graded. Clearing and grubbing should extend to the outside of all proposed excavation and fill areas. Demolition should include removal of buildings, structures, foundations, reservoirs, utilities (including underground pipelines, septic tanks, leach fields, seepage pits, cisterns, mining shafts, tunnels, etc.) and other man-made surface and subsurface improvements from the areas to be graded. Demolition of utilities should include proper capping and/or rerouting pipelines at the project perimeter and cutoff and capping of wells in accordance with the requirements of the governing authorities and the recommendations of the geotechnical consultant at the time of demolition. Trees, plants or man-made improvements not planned to be removed or demolished should be protected by the contractor from damage or injury. Debris generated during clearing, grubbing and/or demolition operations should be wasted from areas to be graded and disposed off-site. Clearing, grubbing and demolition operations should be performed under the observation of the geotechnical consultant. Section 5 - Site Protection Protection of the site during the period of grading should be the responsibility of the contractor. Unless other provisions are made in writing and agreed upon among the concerned parties, completion of a portion of the project should not be considered to preclude that portion or adjacent areas from the requirements for site protection until such time as the entire project is complete as identified by the geotechnical consultant, the client and the regulating agencies. Precautions should be taken during the performance of site clearing, excavations and grading to protect the work site from flooding, ponding or inundation by poor or improper surface drainage. Temporary provisions should be made during the rainy season to adequately direct surface drainage away from and off the work site. Where low areas cannot be avoided, pumps should be kept on hand to continually remove water during periods of rainfall. Rain related damage should be considered to include, but may not be limited to, erosion, silting, saturation, swelling, structural distress and other adverse conditions as determined by the geotechnical consultant. Soil adversely affected should be classified as unsuitable materials and should be subject to overexcavation and replacement with compacted fill or other remedial grading as recommended by the geotechnical consultant. STANDARD SPECIFICATIONS OF GRADING Page 2 of 24 Appendix D Page D-3 Standard Specifications for Grading The contractor should be responsible for the stability of all temporary excavations. Recommendations by the geotechnical consultant pertaining to temporary excavations (e.g., backcuts) are made in consideration of stability of the completed project and, therefore, should not be considered to preclude the responsibilities of the contractor. Recommendations by the geotechnical consultant should not be considered to preclude requirements that are more restrictive by the regulating agencies. The contractor should provide during periods of extensive rainfall plastic sheeting to prevent unprotected slopes from becoming saturated and unstable. When deemed appropriate by the geotechnical consultant or governing agencies the contractor shall install checkdams, desilting basins, sand bags or other drainage control measures. In relatively level areas and/or slope areas, where saturated soil and/or erosion gullies exist to depths of greater than 1.0 foot; they should be overexcavated and replaced as compacted fill in accordance with the applicable specifications. Where affected materials exist to depths of 1.0 foot or less below proposed finished grade, remedial grading by moisture conditioning in-place, followed by thorough recompaction in accordance with the applicable grading guidelines herein may be attempted. If the desired results are not achieved, all affected materials should be overexcavated and replaced as compacted fill in accordance with the slope repair recommendations herein. If field conditions dictate, the geotechnical consultant may recommend other slope repair procedures. Section 6 - Excavations 6.1 Unsuitable Materials Materials that are unsuitable should be excavated under observation and recommendations of the geotechnical consultant. Unsuitable materials include, but may not be limited to, dry, loose, soft, wet, organic compressible natural soils and fractured, weathered, soft bedrock and nonengineered or otherwise deleterious fill materials. Material identified by the geotechnical consultant as unsatisfactory due to its moisture conditions should be overexcavated; moisture conditioned as needed, to a uniform at or above optimum moisture condition before placement as compacted fill. If during the course of grading adverse geotechnical conditions are exposed which were not anticipated in the preliminary soil report as determined by the geotechnical consultant additional exploration, analysis, and treatment of these problems may be recommended. STANDARD SPECIFICATIONS OF GRADING Page 3 of 24 Appendix D . Page D-4 Standard Specifications for Grading 6.2 Cut Slopes Unless otherwise recommended by the geotechnical consultant and approved by the regulating agencies, permanent cut slopes should not be steeper than 2:1 (horizontal: vertical). The geotechnical consultant should observe cut slope excavation and if these excavations expose loose cohesionless, significantly fractured or otherwise unsuitable material, the materials should be overexcavated and replaced with a compacted stabilization fill. If encountered specific cross section details should be obtained from the Geotechnical Consultant. When extensive cut slopes are excavated or these cut slopes are made in the direction of the prevailing drainage, a non-erodible diversion swale (brow ditch) should be provided at the top of the slope. 6.3 Pad Areas All lot pad areas, including side yard terrace containing both cut and fill materials, transitions, located less than 3 feet deep should be overexcavated to a depth of 3 feet and replaced with a uniform compacted fill blanket of 3 feet. Actual depth of overexcavation may vary and should be delineated by the geotechnical consultant during grading, especially where deep or drastic transitions are present. For pad areas created above cut or natural slopes, positive drainage should be established away from the top-of-slope. This may be accomplished utilizing a berm drainage swale and/or an appropriate pad gradient. A gradient in soil areas away from the top-of-slopes of 2 percent or greater is recommended. Section 7 - Compacted Fill All fill materials should have fill quality, placement, conditioning and compaction as specified below or as approved by the geotechnical consultant. 7.1 Fill Material Quality Excavated on-site or import materials which are acceptable to the geotechnical consultant may be utilized as compacted fill, provided trash, vegetation and other deleterious materials are removed prior to placement. All import materials anticipated for use on-site should be sampled tested and approved prior to and placement is in conformance with the requirements outlined. STANDARD SPECIFICATIONS OF GRADING Page 4 of 24 Appendix D Page D-5 Standard Specifications for Grading Rocks 12 inches in maximum and smaller may be utilized within compacted fill provided sufficient fill material is placed and thoroughly compacted over and around all rock to effectively fill rock voids. The amount of rock should not exceed 40 percent by dry weight passing the 3/4-inch sieve. The geotechnical consultant may vary those requirements as field conditions dictate. Where rocks greater than 12 inches but less than four feet of maximum dimension are generated during grading, or otherwise desired to be placed within an engineered fill, special handling in accordance with the recommendations below. Rocks greater than four feet should be broken down or disposed off-site. 7.2 Placement of Fill Prior to placement of fill material, the geotechnical consultant should observe and approve the area to receive fill. After observation and approval, the exposed ground surface should be scarified to a depth of 6 to 8 inches. The scarified material should be conditioned (i.e. moisture added or air dried by continued discing) to achieve a moisture content at or slightly above optimum moisture conditions and compacted to a minimum of 90 percent of the maximum density or as otherwise recommended in the soils report or by appropriate government agencies. Compacted fill should then be placed in thin horizontal lifts not exceeding eight inches in loose thickness prior to compaction. Each lift should be moisture conditioned as needed, thoroughly blended to achieve a consistent moisture content at or slightly above optimum and thoroughly compacted by mechanical methods to a minimum of 90 percent of laboratory maximum dry density. Each lift should be treated in a like manner until the desired finished grades are achieved. The contractor should have suitable and sufficient mechanical compaction equipment and watering apparatus on the job site to handle the amount of fill being placed in consideration of moisture retention properties of the materials and weather conditions. When placing fill in horizontal lifts adjacent to areas sloping steeper than 5:1 (horizontal: vertical), horizontal keys and vertical benches should be excavated into the adjacent slope area. Keying and benching should be sufficient to provide at least six-foot wide benches and a minimum of four feet of vertical bench height within the firm natural ground, firm bedrock or engineered compacted fill. No compacted fill should be placed in an area after keying and benching until the geotechnical consultant has reviewed the area. Material generated by the benching operation should be moved sufficiently away from STANDARD SPECIFICATIONS OF GRADING Page 5of24 Appendix D Page D-6 Standard Specifications for Grading the bench area to allow for the recommended review of the horizontal bench prior to placement of fill. Within a single fill area where grading procedures dictate two or more separate fills, temporary slopes (false slopes) may be created. When placing fill adjacent to a false slope, benching should be conducted in the same manner as above described. At least a 3-foot vertical bench should be established within the firm core of adjacent approved compacted fill prior to placement of additional fill. Benching should proceed in at least 3-foot vertical increments until the desired finished grades are achieved. Prior to placement of additional compacted fill following an overnight or other grading delay, the exposed surface or previously compacted fill should be processed by scarification, moisture conditioning as needed to at or slightly above optimum moisture content, thoroughly blended and recompacted to a minimum of 90 percent of laboratory maximum dry density. Where unsuitable materials exist to depths of greater than one foot, the unsuitable materials should be over-excavated. Following a period of flooding, rainfall or overwatering by other means, no additional fill should be placed until damage assessments have been made and remedial grading performed as described herein. Rocks 12 inch in maximum dimension and smaller may be utilized in the compacted fill provided the fill is placed and thoroughly compacted over and around all rock. No oversize material should be used within 3 feet of finished pad grade and within 1 foot of other compacted fill areas. Rocks 12 inches up to four feet maximum dimension should be placed below the upper 10 feet of any fill and should not be closer than 15 feet to any slope face. These recommendations could vary as locations of improvements dictate. Where practical, oversized material should not be placed below areas where structures or deep utilities are proposed. Oversized material should be placed in windrows on a clean, overexcavated or unyielding compacted fill or firm natural ground surface. Select native or imported granular soil (S.E. 30 or higher) should be placed and thoroughly flooded over and around all windrowed rock, such that voids are filled. Windrows of oversized material should be staggered so those successive strata of oversized material are not in the same vertical plane. It may be possible to dispose of individual larger rock as field conditions dictate and as recommended by the geotechnical consultant at the time of placement. STANDARD SPECIFICATIONS OF GRADING Page 60f24 Appendix D Page D-7 Standard Specifications for Grading The contractor should assist the geotechnical consultant and/or his representative by digging test pits for removal determinations and/or for testing compacted fill. The contractor should provide this work at no additional cost to the owner or contractor's client. Fill should be tested by the geotechnical consultant for compliance with the recommended relative compaction and moisture conditions. Field density testing should conform to ASTM Method of Test D 1556-00, D 2922-04. Tests should be conducted at a minimum of approximately two vertical feet or approximately 1,000 to 2,000 cubic yards of fill placed. Actual test intervals may vary as field conditions dictate. Fill found not to be in conformance with the grading recommendations should be removed or otherwise handled as recommended by the geotechnical consultant. 7.3 Fill Slopes Unless otherwise recommended by the geotechnical consultant and approved by the regulating agencies, permanent fill slopes should not be steeper than 2:1 (horizontal: vertical). Except as specifically recommended in these grading guidelines compacted fill slopes should be over-built two to five feet and cut back to grade, exposing the firm, compacted fill inner core. The actual amount of overbuilding may vary as field conditions dictate. If the desired results are not achieved, the existing slopes should be overexcavated and reconstructed under the guidelines of the geotechnical consultant. The degree of overbuilding shall be increased until the desired compacted slope surface condition is achieved. Care should be taken by the contractor to provide thorough mechanical compaction to the outer edge of the overbuilt slope surface. At the discretion of the geotechnical consultant, slope face compaction may be attempted by conventional construction procedures including backrolling. The procedure must create a firmly compacted material throughout the entire depth of the slope face to the surface of the previously compacted firm fill intercore. During grading operations, care should be taken to extend compactive effort to the outer edge of the slope. Each lift should extend horizontally to the desired finished slope surface or more as needed to ultimately established desired grades. Grade during construction should not be allowed to roll off at the edge of the slope. It may be helpful to elevate slightly the outer edge of the slope. Slough resulting from the placement of individual lifts should not be allowed to drift down over previous lifts. At intervals not STANDARD SPECIFICATIONS OF GRADING Page 7of24 Appendix D Page D-8 Standard Specifications for Grading exceeding four feet in vertical slope height or the capability of available equipment, whichever is less, fill slopes should be thoroughly dozer trackrolled. For pad areas above fill slopes, positive drainage should be established away from the top-of-slope. This may be accomplished using a berm and pad gradient of at least two percent. Section 8 - Trench Backfill Utility and/or other excavation of trench backfill should, unless otherwise recommended, be compacted by mechanical means. Unless otherwise recommended, the degree of compaction should be a minimum of 90 percent of the laboratory maximum density. Within slab areas, but outside the influence of foundations, trenches up to one foot wide and two feet deep may be backfihled with sand and consolidated by jetting, flooding or by mechanical means. If on-site materials are utilized, they should be wheel-rolled, tamped or otherwise compacted to a firm condition. For minor interior trenches, density testing may be deleted or spot testing may be elected if deemed necessary, based on review of backfill operations during construction. If utility contractors indicate that it is undesirable to use compaction equipment in close proximity to a buried conduit, the contractor may elect the utilization of light weight mechanical compaction equipment and/or shading of the conduit with clean, granular material, which should be thoroughly jetted in-place above the conduit, prior to initiating mechanical compaction procedures. Other methods of utility trench compaction may also be appropriate, upon review of the geotechnical consultant at the time of construction. In cases where clean granular materials are proposed for use in lieu of native materials or where flooding or jetting is proposed, the procedures should be considered subject to review by the geotechnical consultant. Clean granular backfill and/or bedding are not recommended in slope areas. Section 9 - Drainage Where deemed appropriate by the geotechnical consultant, canyon subdrain systems should be installed in accordance with CTE's recommendations during grading. Typical subdrains for compacted fill buttresses, slope stabilization or sidehill masses, should be installed in accordance with the specifications. STANDARD SPECIFICATIONS OF GRADING Page 8of24 Appendix D Page D-9 Standard Specifications for Grading Roof, pad and slope drainage should be directed away from slopes and areas of structures to suitable disposal areas via non-erodible devices (i.e., gutters, downspouts, and concrete swales). For drainage in extensively landscaped areas near structures, (i.e., within four feet) a minimum of 5 percent gradient away from the structure should be maintained. Pad drainage of at least 2 percent should be maintained over the remainder of the site. Drainage patterns established at the time of fine grading should be maintained throughout the life of the project. Property owners should be made aware that altering drainage patterns could be detrimental to slope stability and foundation performance. Section 10 - Slope Maintenance 10.1 - Landscape Plants To enhance surficial slope stability, slope planting should be accomplished at the completion of grading. Slope planting should consist of deep-rooting vegetation requiring little watering. Plants native to the southern California area and plants relative to native plants are generally desirable. Plants native to other semi-arid and and areas may also be appropriate. A Landscape Architect should be the best party to consult regarding actual types of plants and planting configuration. 10.2 - Irrigation Irrigation pipes should be anchored to slope faces, not placed in trenches excavated into slope faces. Slope irrigation should be minimized. If automatic timing devices are utilized on irrigation systems, provisions should be made for interrupting normal irrigation during periods of rainfall. 10.3 - Repair As a precautionary measure, plastic sheeting should be readily available, or kept on hand, to protect all slope areas from saturation by periods of heavy or prolonged rainfall. This measure is strongly recommended, beginning with the period prior to landscape planting. If slope failures occur, the geotechnical consultant should be contacted for a field review of site conditions and development of recommendations for evaluation and repair. If slope failures occur as a result of exposure to period of heavy rainfall, the failure areas and currently unaffected areas should be covered with plastic sheeting to protect against additional saturation. STANDARD SPECIFICATIONS OF GRADING Page 9 of 24 Appendix D Page D-10 Standard Specifications for Grading In the accompanying Standard Details, appropriate repair procedures are illustrated for superficial slope failures (i.e., occurring typically within the outer one foot to three feet of a slope face). STANDARD SPECIFICATIONS OF GRADING Page 10 of 24 BENCHING FILL OVER NATURAL SURFACE OF FIRM EARTH MATERIAL FILL SLOPE MI MIN M 10, 15' MIN. (INCLINED 2% MIN. INTO SLOPE) BENCHING FILL OVER CUT SURFACE OF FIRM EARTH MATERIAL FINISH FILL SLOPE FINISH CUT SLOPE 2 10, 0 %MIN TYPICAL' 15' MIN OR STABILITY EQUIVALENT PER SOIL ENGINEERING (INCLINED 2% MIN. INTO SLOPE) NOT TO SCALE BENCHING FOR COMPACTED FILL DETAIL STANDARD SPECIFICATIONS FOR GRADING Page 11 0f24 TOE OF SLOPE SHOWN ON GRADING PLAN FILL - J41 lee eN .00 -.001 I ,I 1 / -. - 10' TYPICAL BENCH WIDTH VARIES COMPETENT EARTH MATERIAL IN TYPICAL BENCH HEIGHT PROVIDE BACKDRAIN AS REQUIRED PER RECOMMENDATIONS OF SOILS ENGINEER DURING GRADING MINIMUM - DOWNSLOPE KEY DEPTH 15' MINIMUM BASE KEY WIDTH WHERE NATURAL SLOPE GRADIENT IS 5:1 OR LESS, BENCHING IS NOT NECESSARY. FILL IS NOT TO BE PLACED ON COMPRESSIBLE OR UNSUITABLE MATERIAL. NOT TO SCALE FILL SLOPE ABOVE NATURAL GROUND DETAIL STANDARD SPECIFICATIONS FOR GRADING Page 12 of 24 NATURAL TOPOGRAPHY CUT SLOPE* REMOVE ALL TOPSOIL, COLLUVIUM, AND CREEP MATERIAL FROM TRANSITION CUT/FILL CONTACT SHOWN ON GRADING PLAN CUT/FILL CONTACT SHOWN ON "AS-BUILT" FILL .01 - - -----.--- 10? 14- TYPICAL - -7 - - - - MIN --, I 15' MINIMUM BEDROCK OR APPROVED FOUNDATION MATERIAL 10' TYPICAL *NOTE: CUT SLOPE PORTION SHOULD BE MADE PRIOR TO PLACEMENT OF FILL NOT TO SCALE FILL SLOPE ABOVE CUT SLOPE DETAIL SIEVE SIZE 1" NO. 30 NO.8 NO. 50 NO. 200 ,i- SURFACE OF / COMPETENT ----------------- C MATERIAL OMPACTED FILL TYPICAL BENCHING REMOVE UNSUITABLE MATERIAL SEE DETAIL BELOW INCLINE TOWARD DRAIN AT 2% GRADIENT MINIMUM DETAIL ------------- MINIMUM 9 FT3 PER LINEAR FOOT MINIMUM 4" DIAMETER APPROVED OF APPROVED FILTER MATERIAL PERFORATED PIPE (PERFORATIONS DOWN) 6" FILTER MATERIAL BEDDING 14" FILTER MATERIAL TO MEET FOLLOWING SPECIFICATION OR APPROVED EQUAL: APPROVED PIPE TO BE SCHEDULE 40 POLY-VINYL-CHLORIDE (P.V.C.) OR APPROVED EQUAL. MINIMUM CRUSH STRENGTH 1000 psi PIPE DIAMETER TO MEET THE FOLLOWING CRITERIA, SUBJECT TO FIELD REVIEW BASED ON ACTUAL GEOTECHNICAL CONDITIONS ENCOUNTERED DURING GRADING LENGTH OF RUN PIPE DIAMETER INITIAL 500' 4" 500' TO 1500' 6" >1500 8" PERCENTAGE PASSING 100 90-100 40-100 25-40 18-33 5-15 0-7 0-3 NOT TO SCALE TYPICAL CANYON SUBDRAIN DETAIL STANDARD SPECIFICATIONS FOR GRADING Page 14 of 24 CANYON SUBDRAIN DETAILS j- SURFACE OF I COMPETENT MATERIAL \ \ COMPACTED FILL TYPICAL BENCHING .00 REMOVE UNSUITABLE MATERIAL SEE DETAILS BELOW INCLINE TOWARD DRAIN AT 2% GRADIENT MINIMUM TRENCH DETAILS 6" MINIMUM OVERLAP OPTIONAL V-DITCH DETAIL - MINIMUM 9 FT3 PER LINEAR FOOT OF APPROVED DRAIN MATERIAL MIRAFI 140N FABRIC OR APPROVED EQUAL MIRAFI 140N FABRIC OR APPROVED EQUAL MINIMUM OVERLAP 24- MjMIMU MINIMUM I ! PER LINEAR FOOT MINIMUM OF APPROVED DRAIN MATERIAL 600 TO 90° APPROVED PIPE TO BE SCHEDULE 40 POLY- VINYLCHLORIDE (P.V.C.) OR APPROVED EQUAL. MINIMUM CRUSH STRENGTH 1000 PSI. DRAIN MATERIAL TO MEET FOLLOWING PIPE DIAMETER TO MEET THE SPECIFICATION OR APPROVED EQUAL: FOLLOWING CRITERIA, SUBJECT TO FIELD REVIEW BASED ON ACTUAL SIEVE SIZE PERCENTAGE PASSING GEOTECHNICAL CONDITIONS ENCOUNTERED DURING GRADING i Y2" 88-100 LENGTH OF RUN PIPE DIAMETER 1" 5-40 INITIAL 500' 4" 3/. 0-17 500' TO 1500' 6' 0-7 > 1500' 8" NO. 200 0-3 NOT TO SCALE GEOFABRIC SUBDRAIN STANDARD SPECIFICATIONS FOR GRADING Page 15 of 24 4" DIAMETER PERFORATED PIPE BACKDRAIN 15' MINIMUM 4" DIAMETER NON-PERFORATED PIPE LATERAL DRAIN SLOPE PER PLAN I " 2.0% FILTER MATERIAL ENCHING (2%MiN !,i ITH H/2 AN ADDITIONAL BACKDRAIN AT MID-SLOPE WILL BE REQUIRED FOR SLOPE IN EXCESS OF 40 FEET HIGH. KEY-DIMENSION PER SOILS ENGINEER (GENERALLY 1/2 SLOPE HEIGHT, 15' MINIMUM) DIMENSIONS ARE MINIMUM RECOMMENDED NOT TO SCALE TYPICAL SLOPE STABILIZATION FILL DETAIL STANDARD SPECIFICATIONS FOR GRADING Page 16 of 24 4" DIAMETER PERFORATED PIPE BACKDRAIN 4" DIAMETER NON-PERFORATED PIPE LATERAL DRAIN 15' MINIMUM SLOPE PER PLAN FILTER MATERIAL \ - 2.0% 'j I BENCHING H12 ADDITIONAL BACKDRAIN AT MID-SLOPE WILL BE REQUIRED FOR SLOPE IN EXCESS OF 40 FEET HIGH. KEY-DIMENSION PER SOILS ENGINEER DIMENSIONS ARE MINIMUM RECOMMENDED NOT TO SCALE TYPICAL BUTTRESS FILL DETAIL STANDARD SPECIFICATIONS FOR GRADING Page 17 of 24 FINAL LIMIT OF DAYLIGHT EXCAVATION LINE FINISH PAD OVEREXCAVATE 3' AND REPLACE WITH COMPACTED FILL OVEREXCAVATE 20' MAXIMUM COMPETENT BEDROCK MIN 2' MINIMUM\ \ 'L TYPICAL BENCHING OVERBURDEN \ \. LOCATION OF BACKDRAIN AND (CREEP-PRONE) \ OUTLETS PER SOILS ENGINEER \ AND/OR ENGINEERING GEOLOGIST \ DURING GRADING. MINIMUM 2% \ FLOW GRADIENT TO DISCHARGE \ LOCATION. EQUIPMENT WIDTH (MINIMUM 15') NOT TO SCALE DAYLIGHT SHEAR KEY DETAIL STANDARD SPECIFICATIONS FOR GRADING Page 18 of 24 ------ - BASE WIDTH "W" DETERMINED BY SOILS ENGINEER COMPACTED FILL PROVIDE BACKDRAIN, PER BACKDRAIN DETAIL. AN ADDITIONAL BACKDRAIN AT MID-SLOPE WILL BE REQUIRED FOR BACK SLOPES IN EXCESS OF 40 FEET HIGH. LOCATIONS OF BACKDRAINS AND OUTLETS PER SOILS ENGINEER AND/OR ENGINEERING GEOLOGIST DURING GRADING. MINIMUM 2% FLOW GRADIENT TO DISCHARGE LOCATION. NATURAL GROUND PROPOSED GRADING NOT TO SCALE TYPICAL SHEAR KEY DETAIL STANDARD SPECIFICATIONS FOR GRADING Page 19 of 24 FINISH SURFACE SLOPE 3 FT MINIMUM PER LINEAR FOOT APPROVED FILTER ROCK CONCRETE COLLAR PLACED NEAT COMPACTED FILL 4" MINIMUM DIAMETER SOLID OUTLET PIPE SPACED PER SOIL ENGINEER REQUIREMENTS DURING GRADING TYPICAL BENCHING - 4" MINIMUM APPROVED PERFORATED PIPE (PERFORATIONS DOWN) MINIMUM 2% GRADIENT TO OUTLET BENCH INCLINED TOWARD DR.AJN 1i1I-w' TEMPORARY FILL LEVEL MINIMUM /7- MINIMUM 4" DIAMETER APPROVED BACKFILL 12" COVEL 12" SOLID OUTLET PIPE 01 MINIMUM *FILTER ROCK TO MEET FOLLOWING APPROVED PIPE TYPE: SPECIFICATIONS OR APPROVED EQUAL: SCHEDULE 40 POLYVINYL CHLORIDE SIEVE SIZE PERCENTAGE PASSING (P.V.C.) OR APPROVED EQUAL. if, ioo MINIMUM CRUSH STRENGTH 1000 PSI 3/. 90-100 V. 40-100 NO.4 25-40 NO. 30 5-15 NO. 50 0-7 NO. 200 10-3 NOT TO SCALE TYPICAL BACKDRAIN DETAIL STANDARD SPECIFICATIONS FOR GRADING Page 20 of 24 FINISH SURFACE SLOPE MINIMUM 3 FT PER LINEAR FOOT OPEN GRADED AGGREGATE* TAPE AND SEAL AT COVER CONCRETE COLLAR PLACED NEAT COMPACTED FILL A ENT II '- MIRAFI 140N FABRIC OR APPROVED EQUAL 4' MINIMUM APPROVED PERFORATED PIPE (PERFORATIONS DOWN) MINIMUM 2% GRADIENT TO OUTLET BENCH INCLINED TOWARD DRAIN MINIMUM 4" DIAMETER SOLID OUTLET PIPE SPACED PER SOIL ENGINEER REQUIREMENTS TYPICAL ' BENCHING %l1AII A A TEMPORARY FILL LEVEL MINIMUM 12" COVER BACKFILL MINIMUM 4" DIAMETER APPROVED SOLID OUTLET PIPE *NOTE: AGGREGATE TO MEET FOLLOWING SPECIFICATIONS OR APPROVED EQUAL: SIEVE SIZE PERCENTAGE PASSING iY2" 100 1" 5-40 L 12- MINIMUM 3/4w 0-17 0-7 NOT TO SCALE NO. 200 0-3 BACKDRAIN DETAIL (GEOFRABIC) STANDARD SPECIFICATIONS FOR GRADING Page 21 of 24 FILL SLOPE CLEAR ZONE a. SOIL SHALL BE PUSHED IOVER ROCKS AND FLOODED INTO VOIDS. COMPACT AROUND AND O • WINDROW. STACK BOULDERS END TO END. DO NOT PILE UPON EACH OTHER. 10, FILL SLOPE STAGGER 15' 10'MIN ROWS /CO,MPE NOT TO SCALE ROCK DISPOSAL DETAIL STANDARD SPECIFICATIONS FOR GRADING Page 22 of 24 FINISHED GRADE BUILDING I SLOPE FACE NO OVERSIZE, AREA FOR 10' FOUNDATION, UTILITIES, 1 AND SWIMMING POOLS p (j STREET cO 15' f 4' WINDROW I 15' -00~ 5' MINIMUM OR BELOW DEPTH OF DEEPEST UTILITY TRENCH (WHICHEVER GREATER) TYPICAL WINDROW DETAIL (EDGE VIEW) GRANULAR SOIL FLOODED TO FILL VOIDS HORIZONTALLY PLACED PROFILE VIEW NOT TO SCALE ROCK DISPOSAL DETAIL STANDARD SPECIFICATIONS FOR GRADING Page 23 of 24 GENERAL GRADING RECOMMENDATIONS CUT LOT ..—ORIGINAL GROUND .0-.00.01 0 - _— TOPSOIL, COLLUVIUM AND WEATHERED BEDROCK 51 . f4 - .01 5' MIN OVEREXCAVATE UNWEATHERED BEDROCK AND REGRADE CUT/FILL LOT (TRANSITION) ORIGINAL ..-GROUND 001.00, MIN 0 - _• -. -. COMPACTED FILL 3'MIN - UNWEATHERED BEDROCK NOT TO SCALE OVEREXCAVATE AND REGRADE TRANSITION LOT DETAIL STANDARD SPECIFICATIONS FOR GRADING Page 24 of 24