Loading...
The URL can be used to link to this page
Your browser does not support the video tag.
Home
My WebLink
About
602256-001; First Responders Joint Use Training Facility; First Responders Joint Use Training Facility; 2008-07-21
GEOTECHNICAL UPDATE INVESTIGATION, PROPOSED CARLSBAD FIRST RESPONDER'S JOINT-USE TRAINING FACILITY, CARLSBAD, CALIFORNIA Prepared For: RRM Design Group 232 Avenida Fabricante, Suite 112 San Clemente, CA 92672 Project No. 602256-001 July 21, 2008 RECEIVED AUG 0 4 2008 CITY OF CARLSBAD PLANNING DEPT Leighton Consulting, Inc. A LEIGHTON GROUP COMPANY mi 4 Leighton Consulting, Inc. A LEIGHTON GROUP COMPANY July 21, 2008 Project No. 602256-001 To: RRM Design Group 232 Avenida Fabricante, Suite 112 San Clemente, CA 92672 Attention: Mr. Don Her A.L A. Subject: Geotechnical Update Investigation, Proposed Carlsbad First Responder's Joint- Use Training Facility, Carlsbad, Califomia In accordance with your request and authorization, we have conducted a geotechnical update investigation of the proposed Carlsbad First Responder's Joint-Use Training Facility, located at 2560 Orion Way in Carlsbad, Califomia. Based on the results of our study, it is our professional opinion that the site is suitable for a proposed development and improvements provided that the recommendations presented herein are incorporated into the design, grading, and constmction of the site. The accompanying report presents a summary of our investigation and provides preliminary geotechnical conclusions and recommendations relative to the proposed site development. If you have any questions regarding our report, please do not hesitate to contact this office. We appreciate this opportunity to be of service. Respectfully submitted, LEIGHTON CONSULTING, INC. William D. Olson, RCE, 4528 Associate Engineer Distribution: (6) Addressee landall K Wagnef, CEG 1612 rincipal Geologist 3934 Murphy Canyon Road, Suite B205 • San Diego, CA 92123-4425 858.292.8030 • Fax 858.292.0771 Mi Section 602256-001 TABLE OF CONTENTS Page 1.0 INTRODUCTION 1 1.1 PURPOSE AND SCOPE 1 1.1.1 Scope of Work 1 1.2 SITE LOCATION AND DESCRIPTION 3 1.3 PREVIOUS SITE DEVELOPMENT ."'. 3 1.4 PROPOSED DEVELOPMENT 3 2.0 SUBSURFACE EXPLORATION AND LABORATORY TESTING 5 3.0 SUMMARY OF GEOTECHNICAL CONDmONS 6 3.1 GEOLOGIC SETTING 6 3.2 SITE-SPECIFIC GEOLOGY e 3.2.1 Artificial Fill - nonstructural (Map Symbol -Afn) 6 3.2.2 Topsoil/ Colluvium (Map Symbol-Qcol) 7 3.2.3 Lusardi Formation (Map Symbol-KI) 7 3.3 GEOLOGIC STRUCTURE [ 8 3.4 SURFACE AND GROUND WATER 8 3.5 LANDSLIDES ......8 3.6 FLOOD HAZARD 9 3.7 ENGINEERING CHARACTERISTICS OF ON-SITE SOILS 9 3.7.1 Expansion Potential 9 3.7.2 Excavation Characteristics 9 3.7.3 Earthworl< Shrinl<age and Bulking n 3.7.4 Soil Corrosivity 12 4.0 FAULTENG AND SEISMICFTY 13 4.1 FAULTING 13 4.2 SEISMICITY 13 4.2.1 Siiallow Ground Rupture 13 4.2.2 Liquefaction 14 4.2.3 Earthquake-Induced Settlement 14 4.2.4 Lateral Spread 14 4.2.5 Tsunamis and Seicfies 15 4.2.6 Building Code Seismic Parameters 15 5.0 CONCLUSIONS 16 6.0 RECOMMENDATIONS 18 6.1 EARTHWORK 18 6.1.1 Site Preparation 18 6.1.2 Removal and Recompaction 18 Leighton Section 602256-001 TABLE OF CONTENTS Page 6.1.3 Excavations and Oversize Material 19 6.1.4 Fill Placement and Compaction 19 6.1.5 Transition Mitigation 20 6.1.6 Expansive Soils and Selective Grading 20 6.1.7 Import Soils 21 6.2 SURFACE DRAINAGE AND EROSION 21 6.3 FOUNDATION AND SLAB CONSIDERATIONS 21 6.3.1 Foundations 22 6.3.2 Slabs 22 6.3.3 Settlement 23 6.3.4 Lateral Pressures and Slioring Design 24 6.4 PRELIMINARY PAVEMENT DESIGN 25 6.5 CoNSTRucnoN OBSERVATION AND TESTING AND PLAN REVIEW 26 7.0 LIMITATIONS 27 TABLES TABLE 1 - EARTHWORK SHRINKAGE AND BULKING ESTIMATES - PAGE 12 TABLE 2 - CBC SEISMIC DESIGN PARAMETERS - PAGE 15 TABLE 3 - STATIC EQUIVALENT FLUID WEIGHT (PCF) - PAGE 24 TABLE 4 - PRELIMINARY ASPHALT PAVEMENT DESIGN - PAGE 25 FIGURE FIGURE 1 - SITE LOCATION MAP - PAGE 2 FIGURE 2 - GEOTECHNICAL MAP - REAR OF TEXT APPENDICES APPENDIX A - REFERENCES APPENDIX B - BORING LOGS AND EXPLORATION TRENCH LOGS APPENDIX C - LABORATORY DATA ANALYSIS APPENDIX D - SEISMIC REFRACHON SURVEY APPENDIX E - GENERAL EARTHWORK AND GRADING SPECIHCATIONS -n- Leighton 602256-001 1.0 INTRODUCTION m lg 1.1 Purpose and Scope il This report presents the results of our geotechnical update investigation of the proposed il Carlsbad First Responder's Joint-Use Training Facility located at 2560 Orion Way in the City of Carlsbad, Califomia. (see Figure 1). Our investigation included geotechnical • exploration of the site, laboratory testing of selected soil samples, geotechnical analysis of Ml the data collected, and preparation of this report. The purpose of our geotechnical investigation was to evaluate existing geotechnical conditions present at the site and to provide preliminary conclusions and geotechnical recommendations relative to the proposed development of the property. 1.1.1 Scope of Work As part of our geotechnical investigation, we performed the following: • Review of available pertinent, published, and unpublished geotechnical literature maps, and aerial photographs (Appendix A). • Review of the previous investigation and as-graded reports (Leighton, 2001), and conceptual site development plans by RRM Design Group (RRM, 2008). • Field reconnaissance of the existing onsite geotechnical conditions. • Coordination with Underground Services Alert (USA) to locate potential underground utilities on or adjacent to the site. • Subsurface exploration consisting of the excavation, logging, and sampling of 9 hollow-stem auger borings. The approximate borings are shown on the Geotechnical Map (Figure 2). The logs of the borings are presented in Appendix B. • Laboratory testing of representative soil samples obtained from the subsurface exploration. Results of these tests are presented in Appendix C, with the exception of moisture/density determinations, which are provided on the boring logs (included in Appendix B). • Compilation and analysis of the geotechnical data obtained from the field investigation and laboratory testing (including the prior seismic refraction survey presented in Appendix D). -1- Leighton 4,000 Carlsbad First Responder's Joint-UseTraining Facility City of Carlsbad, California SITE LOCATION MAP Project No. 602256-001 Date July 2008 4 Figure 1 \\GIS\Administration\ArcGISTemplates\NEW_GDT_SiteLocationMap.mxd ii 602256-001 Review local and regional seismicity, and provide seismic parameters for the site in accordance with 2007 Califomia Building Code (CBC). Preparation of this report presenting our findings, conclusions, and geotechnical recommendations with respect to the proposed design, site grading and general constmction considerations. 1.2 Site Location and Description The site, which is bounded by Orion Way on the north, south and east sides, and Orion Street to the west is located in the east-central portion of Carlsbad, Califomia (Figure 1). Currently, the site is being used as an athletic field (baseball and soccer) with minor fill slopes at the north-eastem and south-westem comers. At the eastem end of the site, there is an elevated grassy area with trees and large exposed landscape boulders. Topography of the athletic field is generally flat with elevations ranging from approximately 351 feet to 357 feet mean sea level (msl) at the westem and eastem ends, respectively. The elevation of the elevated grassy area is approximately 365 feet msl. 1.3 Previous Site Development The original mass-grading of the general site was performed in 1985 and generally consisted of cuts and fills for the existing buildings and parking areas, and infilling of the previously existing canyon located in the southeast portion of the Carlsbad Public Works Facility. Reportedly, uncontrolled artificial fill containing oversize materials (i.e. boulders) was placed at the subject site (the athletic field and the elevated grassy area) within the area bounded by Orion Way and Orion Street. In 1988, rough grading for the if existing City of Carlsbad Fire Station No. 5 and the existing skate park located at the southem portion of the site was performed. As background, the grading operations for the existing fire station were performed during July and August, 1988 under the observation of Leighton and Associates, Inc. (Leighton, 1988). IM 1.4 Proposed Development Based on our review of the conceptual site development plans, prepared by RRM, dated May 2008, we understand that the proposed development consists of a total area of approximately 4.3 acres. The proposed training facility will consist of four major elements: a Residential Bum Prop Stmcture, a Commercial Bum Prop Stmcture (with a multi-story training tower), a classroom and shooting range building, and a one- to two- story Fire Administration building. 4 •3- Leighton 602256-001 We are assuming that the buildings and training stmctures will be constmcted with masonry or concrete walls. Other proposed improvements consist of training pavement areas adjacent to the buildings, court yards, sidewalks, underground utilities, and landscape areas. Proposed grades of the development are assumed to remain at or near the present elevations. m 4 Leighton 602256-001 2.0 SUBSURFACE EXPLORATION AND LABORATORY TESTING Our recent subsurface investigation consisted of the excavation of nine (9) small-diameter exploratory borings. The purpose of these excavations was to evaluate the engineering characteristics of the onsite soils with regard to the proposed development. The borings allowed evaluation of the onsite soils, including those likely to be encountered at the proposed foundation elevations and provided representative samples for laboratory testing. The exploratory excavations were logged by a representative from our firm. Representative bulk and relatively undisturbed samples were obtained at frequent intervals for laboratory testing. The approximate locations of the borings are shown on the Geotechnical Map (Figure 2). Subsequent to logging and sampling, the borings were backfilled with bentonite in general accordance with the County of San Diego, Department of Environmental Health (DEH) requirements. Laboratory testing was performed on representative samples to evaluate moisture and density, soil strength parameters, hydraulic conductivity (permeability), and geochemical characteristics of the subsurface soils. A discussion of the laboratory tests performed and a summary of the laboratory test results are presented in Appendix C. In-situ moisture and density test results are provided on the boring logs (Appendix B). It should be noted that a previous subsurface investigation and geotechnical study of the site and an area north of the site was performed by Leighton in 2001. As part of that previous study, two trenches, T-3 and T-4, were excavated, sampled and logged in the vicinity of the currentiy proposed im_provements. Depths of trenches ranged from 5 to 8 feet below the existing ground surface (bgs). Trench logs are presented in Appendix B. In addition, a seismic refraction survey was performed by Subsurface Surveys for the previous study. The refraction survey consisted of eight seismic traverses, of which four seismic traverses (Lines 5, 6, 7 and 8) are within the current study area (Leighton, 2001). The seismic refraction survey report is presented in Appendix D. The approximate locations of the previous trenches and seismic traverses are shown on the Geotechnical Map (Figure 2). 4 -5- Leighton 602256-001 3.0 SUMMARY OF GEOTECHNICAL CONPmONS 3.1 Geologic Setting The subject site is located in the coastal section of the Peninsular Range Province, a geomorphic province with a long and active geologic history throughout Southem Califomia. The area known as the "San Diego Embayment" has undergone several episodes of marine inundation and subsequent marine regression, resulting in the deposition of a thick sequence of marine and nonmarine sedimentary rocks on the basement rock of the Southem Califomia batholith. Gradual emergence of the region from the sea occurred in Pleistocene time, and numerous wave-cut platforms, most of which were covered by relatively thin marine and nonmarine terrace deposits, formed as the sea receded from the land. Accelerated fluvial erosion during periods of heavy rainfall, coupled with the lowering of the base sea level during Quatemary time, resulted in the rolling hills, mesas, and deeply incised canyons which characterize the landforms we see in the general site area today. 3.2 Site-Specific Geology Based on our subsurface exploration, and review of pertinent geologic literature and maps, the site is generally overlain by undocumented artificial fill soils which is underlain by topsoil/colluvium and/or bedrock material consisting of the Lusardi Formation. A brief description of the geologic units as encountered on the site is presented below. The approximate aerial distributions of these units are shown on the Geotechnical Map (Figure 2). 3.2.1 Artificial Fill - nonstructural (Map Svmbol -Afn^ Based on our review of the as-graded geotechnical report for the site, we understand that placement of uncontrolled nonstmctural artificial fill was generally limited to the present ball field and grassy area within the area bounded by Orion Way and Orion Street. The approximate limits of uncontrolled nonstmctural fill are shown on the Geotechnical Map (Figure 2). As encountered during our investigation, the nonstmctural fill soils generally consist of dry to moist; loose to dense; clayey, silty sand with scattered gravel. Nonstmctural fill soils were encountered to depths ranging from approximately 2 to 5 feet bgs in the Borings and previous Trenches T-3 and T-4 (Appendix B); however, deeper fills may exist and could be encountered during site grading. 4 -6- Leighton 602256-001 Note that it is our understanding that this area was also utilized for stockpiling oversize materials during grading and that the stockpile was covered with uncontrolled fill near the completion of grading (Geocon, 1985). These non- stmctural fill soils are considered potentially compressible in their current state and will require complete removal and recompaction within the limits of site grading. These soils appear to be suitable for use as fill provided they are relatively free of rocks (larger than 8-inches in maximum dimension) organic material, and deleterious debris. Special handling recommendations for oversize material are included in Appendix E. 3.2.2 Topsoil/Colluvium (Map Svmbol-Ocoh As encountered, the topsoil/colluvium on the site consists of dark gray, dark brown to brown and yellow, moist to damp, stiff sandy clay and loose to very dense, slightiy clayey silty sand with some organic debris. Observations also indicated that the lower portion of this unit was locally porous. In general, the topsoil/colluvium was found to be generally indistinguishable in the upper portion of this unit. This material was found underlying undocumented fill soils in Trenches T-3 and T-4 and is likely to be present in other areas of the site. In general, the topsoil/colluvial soils were found to range from 1 to 3.5 feet in thickness. However, the deeper accumulation of this unit could be encountered. To supplement our previous 2001 subsurface investigation, a seismic refraction survey was performed, as described in Section 3.7.2 of this report. The results of the seismic refraction survey within the subject site indicate the thickness of the uncontrolled fill and topsoil/colluvium varies from approximately 3 to 12 feet in the vicinity of Line 5 through 8 (Appendix D). In general, the topsoil/colluvium is considered potentially compressible and not suitable for support of the proposed improvements. This material will need to be removed to competent formational material in areas of proposed improvements. It should also be noted that the clayey portions of this material may have a high expansion potential (Leighton, 2001). 3.2.3 Lusardi Formation fMap Svmbol-Kh The Cretaceous-aged Lusardi Formation underlies the site at depth and is considered to be the primary bedrock unit at the site. The Lusardi Formation is generally composed of light brown to gray brown, and orange to red-brown; very dense; gravel to cobble and boulder conglomerate with a medium to coarse sandstone matrix. The gravel to boulder clasts in this unit are predominately 4 ^ Leighton 602256-001 composed of granitic material derived from the underlying granitic bedrock. The Lusardi Formation generally mantels the underlying granitic bedrock and locally contains large to very large (up to 10 to 20 feet in diameter) granitic boulders. These granitic boulders are commonly very dense and, if encountered, may cause excavation difficulties during grading. Although not believed to be common, local beds of claystone and siltstone may also be encountered in this unit. The Lusardi Formation is generally expected to exhibit favorable engineering properties. Excavation of this material may be difficult in areas; however, based on our review of the proposed site plans, deep cuts in this unit are not anticipated. If oversized materials are generated during grading they should be handled in accordance with the recommendations presented herein and in Appendix E of this report. 3.3 Geologic Structure The Lusardi Formation bedrock encountered on the site was generally massive with no apparent bedding. 3.4 Surface and Ground Water No indication of surface water or evidence of surface ponding was encountered during our field investigation. However, surface water may drain as sheet flow across the sheet- graded pad during rainy periods and accumulate in lower elevations of the site. Ground water was not observed in the borings during our investigation; however, perched ground water should be anticipated on top of the Lusardi Formation and may fluctuate during periods of precipitation. In addition, saturated areas and seepage along the northem perimeter of the site (i.e., at the toe of the existing slope) may develop during rainy periods. It should be noted that laboratory testing of the remolded fill soils (sample remolded to approximately 90 percent relative compaction of ASTM 1557) indicate a hydraulic conductivity on the order of 0.000021-cm/sec. ^ 3.5 Landslides m No ancient landslides have been mapped on the subject site. In addition, no evidence of landsliding was encountered during our site investigation. Based on the flat nature of the site and our experience with similar conditions in the project vicinity, the potential for landsliding is considered low. 4 -8- Leighton Ml 602256-001 3.6 Flood Hazard According to a Federal Emergency Management Agency (FEMA) flood insurance rate map (FEMA, 1997), the site is not located within a flood zone. Based on review of dam inundation and topographic maps per SANGIS, the site is not located downstream from dam inundation areas. 3.7 Engineering Characteristics of On-site Soils Based on the results of our geotechnical investigation, previous geotechnical investigations of the site by others, laboratory testing of representative on-site soils, and our professional experience on adjacent sites with similar soils, the engineering characteristics of the on-site soils are discussed below. 3.7.1 Expansion Potential The majority of the onsite soils are expected to have a low to moderate expansion potential. However, clayey portions of the existing topsoil/colluvium were previously tested to be highly expansive (Leighton, 2001). Geotechnical observation and/or laboratory testing upon completion of the graded pads is recommended to determine the actual expansion potential of finish grade soils on the graded building pads. These materials should be placed at depths greater than 5 below pad grade and at least 3 feet below parking/drive areas, streets and/or hardscape areas. 3.7.2 Excavation Characteristics As part of the previous investigation for the site, a seismic refraction field study was conducted on August 10, 2001. A total of 1,816 linear feet of data was collected along eight seismic refraction lines. The purpose of these surveys was to evaluate the approximate seismic velocities of the Lusardi Formation material in order to provide a rough estimate of the rippability characteristics of the formational materials. The approximate locations of the seismic survey lines are presented on the Geotechnical Map (Figure 2) and the results presented in Appendix D. The seismic refraction method uses first-arrival times of refracted seismic waves to determine the thickness and seismic velocities of subsurface materials. The seismic waves were initiated at the ends of each survey line by striking an aluminum plate with a 20-pound hammer. Seismic waves generated at the ground surface were -9- Leighton 602256-001 reflected and refracted from boundaries separating materials of contrasting velocities (or densities) and were detected by a series of twenty-four surface geophones placed along the survey line. The waves detected by the geophones were recorded with a Bison 9024, 24 channel seismograph. Time-distance plots and associated geophysical interpretations of the seismic data from the eight survey lines were then prepared and analyzed. The data is provided in Appendix D. It should be noted that the measured seismic velocities presented on the plots represent average velocities of the subsurface materials, and significant local variations due to buried boulders (or "floaters"), localized hard or cemented zones concretions, or other anomalies may be present. In order to categorize the subsurface materials in terms of excavation characteristics, the following classifications are utilized. This five-fold classification scheme is based on our experience with similar rocks in the San Diego County area, and assumes the use of a single shank D9L Dozer (or equivalent equipment). The rippability characteristics of the site materials are classified as follows: Calculated Seismic Velocity Up to 2000 feet per second 2000 to 4000 feet per second 4000 to 5500 feet per second 5500 to 7000 feet per second Greater than 7000 feet per second General Excavation Characteristic Easy ripping Moderately difficult ripping Difficult ripping, possible localized blasting Very difficult ripping, probable local to general blasting Blasting required "Difficult ripping" refers to rocks, m which it becomes difficult to achieve tooth penetration, sharply reducing ripping production. Local blasting may be necessary in order to maintain a desired ripping production rate. "Very difficult ripping" refers to rocks in which the use of heavy constmction equipment is likely to cease being a cost-effective method of excavation (necessitating the use of explosives to maintain a desired excavation rate). It should be emphasized that the cutoff velocities of this classification scheme are approximate and rock characteristics (such as fracture or joint spacing and orientation) play a significant role in determining rock rippability. These characteristics may also vary with location and depth in the rock mass. -10-4 Leighton 602256-001 The average seismic velocities of the underlying Lusardi Formation along the four seismic survey lines varies from approximately 4585 to 5502. Based on the results of the seismic refraction study, it appears that near surface materials are rippable with heavy-duty constmction equipment in good working order (i.e. a single shank D9L Dozer or equivalent). Difficult ripping and possible localized blasting may be required and should generally be limited to areas of deep utility excavations. However, deep cuts into the Lusardi Formation are not anticipated during the grading operations. If a significant amount of oversize material (typically rock over 8 inches in maximum dimension) is generated, it should be placed in accordance with Section 6.1.2 of this report and Appendix E. 3.7.3 Earthwork Shrinkage and Bulking Based on the results of our investigation and our professional experience with similar projects in the general vicinity of the site, we have estimated bulking and shrinkage of the on-site soils. The thickness of uncontrolled artificial fill is unknown but anticipated to be on the order of 2 to 5 feet in depth. In addition, topsoil/colluvial soils may underlie the uncontrolled artificial fill, and are generally anticipated to be on the order of 1 to 4 feet thick. The volume change of excavated onsite materials upon recompaction as fill is expected to vary with materials and location. Typically, the surficial soils and bedrock materials vary significantiy in natural and compacted density, and therefore, accurate earthwork shrinkage^ulking estimates cannot be determined. However, the following factors (based on the results of our investigation, geotechnical analysis and professional experience with similar materials) are provided on Table 1 as guideline estimates. If possible, we suggest an area where site grades can be adjusted (during the later portion of the site grading operations) be provided as a balance area. •11- Leighton 602256-001 Table 1 Earthwork Shrinkage and Bulking Estimates Geologic Unit Estimated Shrinkage/bulking Undocumented Fill 5 to 15 percent shrinkage Topsoil/Colluvium 0 to 10 percent shrinkage Lusardi Formation 4 to 12 percent bulking 3.7.4 Soil Corrosivity A preliminary corrosive soil screening for the on-site fill soil was performed to evaluate the potential effect on concrete and ferrous metals. Laboratory testing was performed on one representative sample to evaluate pH, minimum electrical resistivity, and chloride and soluble sulfate contents. The sample tested had a measured pH of 7.39, and a measured minimum electrical resistivity of 6,000 ohm-cm. Test results also indicated that the sample had a chloride content of 84 ppm, and a soluble sulfate content of 180 ppm. •12-4 Leighton 602256-001 4.0 FAULTING AND SEISMICITY 4.1 Faulting Our discussion of faults on the site is prefaced with a discussion of Califomia legislation and state policies concerning the classification and land-use criteria associated with faults. By definition of the Califomia Mining and Geology Board, an active fault is a fault which has had surface displacement within Holocene time (about the last 11,000 years). The state geologist has defined a potentiallv active fault as any fault considered to have been active during Quatemary time (last 1,600,000 years). This definition is used in delineating Earthquake Fault Zones (EFZ) as mandated by the Alquist-Priolo Earthquake Faulting Zones Act of 1972 and as most recentiy revised in 1997 (Hart, 1997). The intent of this act is to assure that unwise urban development and certain habitable stmctures do not occur across the traces of active faults. Based on our review, the site is not located within an EFZ (CGS, 2003). A review of available geologic literature pertaining to the subject site indicates that there are no known active regional faults that transect the subject site (Appendix A). The nearest known active regional fault is the Rose Canyon Fault located approximately 7 miles west of the site (Blake, 2000). 4.2 Seismicity The principal seismic considerations for most stmctures in southem Califomia are surface mpturing of fault traces and damage caused by strong ground shaking or seismically induced ground settlement. Historically, the San Diego region has been spared major destmctive earthquakes. The site is considered to lie within a seismically active region, as can all of Southem Califomia. The effect of seismic shaking may be mitigated by adhering to the Califomia Building Code (see Section 4.2.6 of this report for CBC seismic parameters) or state-of-the-art seismic design parameters of the Stmctural Engineers Association of Califomia. Secondary effects associated with severe ground shaking following a relatively large earthquake can include shallow ground mpture, soil liquefaction, lateral spreading, earthquake-induced settlement, and tsunamis/seiches. These secondary effects of seismic shaking are discussed in the following sections. 4.2.1 Shallow Ground Rupture No active or potentially faults are mapped transecting the site, and the site is not located within a mapped EFZ (CGS, 2003). The nearest mapped active fault is the 4 -13- Leighton 602256-001 Rose Canyon Fauh located approximately 7 miles west of the site. Ground cracking due to shaking from distant seismic events is not considered a significant hazard at the site, since the site is underlain at depth by dense sedimentary formation and there are no significantly high slopes on the site or adjacent to the site. 4.2.2 Liquefaction Liquefaction and dynamic settlement of soils can be caused by strong vibratory motion due to earthquakes. Both research and historical data indicate that loose, saturated, granular soils are susceptible to liquefaction and dynamic settlement. Liquefaction is typified by a total loss of shear strength in the affected soil layer. Liquefaction may be manifested by sand boils, excessive settlement, and bearing failure. Bedrock materials at the site are not considered liquefiable due to either their high density or unsaturated conditions. Surficial materials including undocumented fill and topsoil/ colluvium are recommended for removal and replacement with compacted engineered fill material. Properly compacted engineered fill is not considered to be liquefiable. 4.2.3 Earthguake-Induced Settlement Granular soils tend to densify when subjected to shear strains induced by ground shaking during earthquakes. Simplified methods were proposed by Tokimatsu and Seed (1987) and Ishihara and Yoshimine (1991) involving SPT N-values used to estimate earthquake-induced soil settlement. Due to the low susceptibility of the site to liquefaction, the potential for earthquake-induced settlements is considered to be low during strong ground shaking. Earthquake-induced settlements tend to be most damaging when differential settlements result. Earthquake-induced total and differential settlement are expected to be negligible. 4.2.4 Lateral Spread Empirical relationships have been derived by Youd and others (Youd, 1993; Bartlett and Youd, 1995; and Youd et. al., 1999) to estimate the magnitude of lateral spread due to liquefaction. These relationships include parameters such as earthquake magnitude, distance of the earthquake from the site, slope height and angle, the thickness of liquefiable soil, and gradation characteristics of the soil. 4 -14- Leighton 602256-001 Since the potential for liquefaction at the site is low, the susceptibility to earthquake-induced lateral spread is also considered to be low. 4.2.5 Tsunamis and Seiches Based on the distance between the site and large, open bodies of water, barriers between the site and the open ocean, and the elevation of the site with respect to sea level, the possibility of seiches and/or tsunamis is considered to be nil. 4.2.6 Building Code Seismic Parameters The following table below presents geotechnical design parameters that have been determined in accordance with the 2007 CBC (CBSC, 2007). Table 2 CBC Seismic Design Parameters Description Values CBC Reference Site Class c Table 1613.5.2 Short Period Spectral Acceleration Ss 1.300 Figure 1613.5(3) 1-Second Period Spectral Acceleration Si 0.491 Figure 1613.5(4) Short Period Site Coefficient Fa 1.0 Table 1613.5.3(1) 1-Second Period Site Coefficient Fv 1.309 Table 1613.5.3(2) Adjusted Short Period Spectral Acceleration SMS 1.300 Equation 16-37 Adjusted 1-Second Period Acceleration SMI 0.642 Equation 16-38 Design Short Period Spectral Response Parameter SDS 0.866 Equation 16-39 Design 1-Second Period Spectral Response Parameter SDI 0.428 Equation 16-40 -15-4 Leighton 602256-001 5.0 CONCLUSIONS Based on the results of our geotechnical investigation of the site, it is our professional opinion that the proposed development of the site is feasible from a geotechnical standpoint, provided the following conclusions and recommendations are incorporated into the design, grading, and constmction of the project. The following is a summary of the geotechnical factors that may affect development of the site. • Based on our reference review, subsurface exploration, and laboratory testing, uncontrolled nonstmctural artificial fill was placed during the 1985 rough grading of the site. In addition, potentially compressible topsoil/colluvium was left-in-place and currently underlies the uncontrolled fill in various areas. The uncontrolled fill, topsoil/colluvium are considered potentially compressible in their current state and will require complete removal to competent formational material in areas of proposed settlement sensitive improvements. • In general, the on-site soils appear to be suitable for reuse as fill provided they are relatively free of rocks (larger than 8-inches in maximum dimension) organic material, and deleterious debris. • Near surface materials are considered rippable with heavy-duty constmction equipment in good working order (i.e. a single shank D9L Dozer or equivalent). Difficult ripping and possible localized blasting may be required and should generally be limited to areas of deep utility excavations. Excavations exceeding 10 feet within the Lusardi Formation may require very heavy ripping and probable local to general blasting. However, deep cuts into the Lusardi Formation are not anticipated during the grading operations. • Oversized material (requiring specialized handling) may be generated during demolition of the existing improvements, excavation within the Lusardi Formation, and grading operations • within uncontrolled (nonstmctural) fill areas. • The uncontrolled fill soils and soils of the Lusardi Formation are anticipated to have a low to medium expansion potential. ^ • Clayey topsoil and colluvial soils may be moderately to highly expansive and are not recommended for use as compacted fill below proposed building areas, as subgrade material for m the parking and drive areas, or as retaining wall backfill. * • Laboratory test results indicate that fill soil present on the site have a negligible potential for m sulfate attack concrete and a relatively mild or low potential for corrosion to buried uncoated m metal conduits. Additional laboratory testing should be performed during grading. 4 -16- Leighton 602256-001 Ground water was not encountered during our investigation. Although not encountered during our investigation, perched ground water may occur locally on top of the Lusardi Formation, particularly after periods of heavy rainfall or irrigation. Groundwater is not expected to significantly impact the proposed development provided the recommendations regarding drainage outlined in this report are implemented. The site is located in an area underlain by the Lusardi Formation that is known to contain both permeable and impermeable layers which can transmit and perch ground water in unpredictable ways. Therefore, given the site geologic conditions. Low hnpact Development (LID) measures may impact down gradient area, which include existing improvements (buildings and utilities) and potential fiiture developments adjacent properties. Therefore, the use of some LID measures may not be appropriate for this project. 4 -17- Leighton 602256-001 «« 6.0 RECOMMENDATIONS m 6.1 Earthwork We anticipate that earthwork at the site will consist of site preparation, minor cuts and M fills and underground utility excavation. We recommend that earthwork on the site be performed in accordance with the following recommendations and the General Earthwork and Grading Specifications for Rough Grading included in Appendix E of this report. In case of conflict, the following recommendations shall supersede those in Appendix E of this report. m 6.1.1 Site Preparation • Prior to grading, all areas to receive stmctural fill or engineered stmctures should ^ be cleared of surface and subsurface obstmctions; including any existing utilities, debris, and nonstmctural, undocumented or loose fill soils, and stripped of " vegetation. Removed vegetation and debris should be properly disposed off site. ^ Holes resulting from removal of buried obstmctions that extend below finish ^ grades should be replaced with suitable compacted fill material. All areas to receive fill and/or other surface improvements should be scarified to a minimum ^ depth of 6 inches, brought to at least 2 percent above near-optimum moisture ^ conditions, and recompacted to at least 90 percent relative compaction (based on ASTM Test Method D1557). *" 6.1.2 Removal and Recompaction ^ The existing undocumented fills, nonstmctural fill soils, and topsoil/colluvium are considered potentially compressible and are not suitable for support of the m proposed improvements. Where not removed by the plaimed grading, these soils H should be excavated to competent formational material bedrock as determined by Leighton. The removal bottom should be moisture-conditioned and recompacted ii to a minimum 90 percent relative compaction (based on ASTM Test Method il D1557) prior to placing fill. The removal limit should be established by a 1:1 projection from the edge of fill soils supporting settlement-sensitive stmctures •» downward and outward to competent material identified by the geotechnical •1 consultant. In general, we anticipate the depth of removals to be on the order of 2 to +10 feet across the site, and may be deeper in localized areas. All removal bottoms should be reviewed by the geotechnical consultant prior to fill placement. 4 -18- Leighton iii 602256-001 6.1.3 Excavations and Oversize Material Shallow excavations of the onsite materials may generally be accomplished with conventional heavy-duty earthwork equipment. Based on the results of the seismic refraction study and our review of previous geotechnical reports, excavations exceeding 10 feet with the Lusardi Formation may require very heavy ripping and/or blasting and may result in the generation of some oversize material. In addition, cemented zones and granitic floaters may likely be encountered in deeper excavation within this unit. Due to the high-density characteristics of the onsite Lusardi Formation, temporary excavations such as utility trenches with vertical sides in these units should remain stable for the period required to constmct the utility, provided they are free of adverse geologic conditions. Undocumented and nonstmctural artificial fill and topsoil/colluvial soils present on site may cave during trenching operations. In accordance with OSHA requirements, excavations deeper than 5 feet should be shored or be laid back if workers are to enter such excavations. Temporary sloping m gradients should be determined in the field by a "competent person" as defined by OSHA. For preliminary planning, sloping of surficial soils at 1 to 1 (horizontal to ^ vertical) may be assumed. Excavations greater than 20 feet in height will require ^ an altemative sloping plan or shoring plan prepared by a Califomia registered civil engineer. Excavation safety is the responsibility of the contractor. ^ We anticipate that oversize material may be generated during demolition of existing improvements, excavation within the Lusardi Formation, and grading operations within uncontrolled (nonstmctural fill areas). Recommendations for «- treatment of oversize material are included in the attached General Earthwork and ^ Grading Specifications for Rough Grading (Appendix E). Excavated materials with oversize boulders derived from the Lusardi Formation would necessitate selective grading measures. In general, oversize material may be utilized in ^ approved surface applications or hauled off site. 6.1.4 Fill Placement and Compaction The onsite granular soils are generally suitable for use as compacted fill provided they are free of organic material, debris, and rock fragments larger than 8 inches in maximum dimension. All fill soils should be brought to at least 2 percent above optimum moisture conditions and compacted in uniform lifts to at least 90 percent relative compaction based on laboratory standard ASTM Test Method D1557. For parking areas, we recommend that the upper 12 inches of subgrade soils be compacted to at least 95 percent (based on ASTM Test Method D1557). The optimum lift thickness required to produce a uniformly compacted fill will depend 4 -19- Leighton 602256-001 on the type and size of compaction equipment used. In general, fill should be placed in lifts not exceeding 8 inches in thickness. The onsite soils typically possesses a moisture content below optimum and may require moisture conditioning prior to use as compacted fill. Localized areas of overly wet material should be anticipated in previously landscaped areas or within clayey colluvial soils. In general, overly wet material should be dried back and/or replaced with granular import soils. Placement and compaction of fill should be performed in general accordance with the current City of Carlsbad grading ordinances, sound constmction practice, and the General Earthwork and Grading Specifications for Rough Grading presented in Appendix E. ^ 6.1.5 Transition Mitigation m We anticipate that a transition from cut to fill may be developed beneath the In proposed classroom/shoot range building and the Fire Administration building. In order to reduce the potential for differential settlement, we recommend that the m entire cut portion of transition within the building pad areas be overexcavated to a Ii minimum depth of 2 feet below the lowest proposed footing elevation and replaced with properly compacted fill of very low to low expansion potential. The overexcavation and recompaction should laterally extend a minimum of 5 feet IM beyond the building perimeter. The base of the overexcavated portion of the building pad should slope at approximately 2 percent toward the fill side to ^ mitigate the potential for accumulation that may result from surface infiltration, i-i Similar treatment should be anticipated for proposed buildings that overlie ^ backfilled cavities following demolition activities. • As an altemative to overexcavation beneath the building pad, all footings may be ^ extended a minimum depth of 12 inches into competent bedrock under the observation of the geotechnical consultant. * 6.1.6 Expansive Soils and Selective Grading The onsite soils are expected to have a low to very high expansion potential. If expansive soils are utilized at grade, typical expansive soil-related distress (such as cracked flatwork and stucco, poor vegetation growth, etc.) may be expected over the life of the project. Accordingly, we recommend that high or very high expansive soils encountered during grading operations be placed in fill areas below a minimum depth of 5 feet measured from the finish grade of the proposed IP building pads and 3 feet in drive/parking areas, streets, and hardscape and not 4 -20- Leighton 602256-001 within 15 feet of the face of any slope. Expansive soils exposed at finish pad elevations should likewise be removed to a depth of 5 feet and replaced with low expansion potential compacted fill unless special foundation design recommendations for expansive soil are implemented. 6.1.7 Import Soils If import soils are necessary to bring the site up to proposed grade, these soils should be granular and have an Expansion Index less than 50 per ASTM Test Method D4829 (i.e. a very low to low expansion potential). Please contact this office for fiirther evaluation of the borrow site prior to import. 6.2 Surface Drainage and Erosion Surface drainage should be controlled at all times. The proposed stmcture should have an appropriate drainage system to collect roof runoff. Positive surface drainage should be provided to direct surface water away from the stmcture toward the street or suitable drainage facilities. Planters should be designed with provisions for drainage to the storm drain. Ponding of water should be avoided adjacent to the stmcture. Regarding Low Impact Development (LID) measures, we are of the opinion that bioswales, infiltration basins, and other onsite retention and infiltration systems can potentially create adverse perched ground water conditions both on-site and off-site. In particular, this site is underlain by Lusardi Formation that is known to contain both permeable and impermeable layers which can transmit and perch ground water in unpredictable ways. Therefore, given the site geologic conditions and project type, some LID measures may not be appropriate for this site and project. 6.3 Foundation and Slab Considerations Foundations and slabs should be designed in accordance with stmctural considerations and the following recommendations. These recommendations assume that the soils ii encountered within 5 feet of pad grade have a low to medium potential for expansion. Additional expansion testing should be performed as part of the fine grading operations. If highly expansive soils are encpuntered and selective grading cannot be accomplished, il additional foundation design may be necessary. ii 4 -21- Leighton 602256-001 6.3.1 Foundations We anticipate that the proposed stmctures can be supported by isolated spread and/or continuous footings. Footings should extend a minimum of 24 inches beneath the lowest adjacent finish grade. At these depths, footings may be designed for a maximum allowable bearing pressure of 2,500 pounds pounds square foot (psf) if founded entirely in properly compacted fill soils. An allowable capacity increase of 250 psf for every 6 inches of additional width and embedment depth may be used, not exceeding 3,500 psf. Where all building foundations are extended to competent bedrock, an allowable bearing pressure of 4,000 psf may be used. The bearing pressure for site walls should be limited to 2,000 psf The allowable pressures may be increased by one-third when considering loads of short duration such as wind or seismic forces. The minimum recommended width of footings is 18 inches for continuous footings and 24 inches for square or round footings. Footings should be designed in accordance with the stmctural engineer's requirements and have a minimum reinforcement of four No. 5 reinforcing bars (two top and two bottom). We recommend a minimum horizontal setback distance from the face of slopes for all stmctural footings and settlement-sensitive stmctures. This distance is measured from the outside edge of the footing, horizontally to the slope face (or to the face of a retaining wall) and should be a minimum of H/2, where H is the slope height (in feet). The setback should not be less than 10 feet. Please note that the soils within the stmctural setback area possess poor lateral stability, and improvements (such as retaining walls, sidewalks, fences, pavements, etc.) constmcted within this setback area may be subject to lateral movement and/or differential settlement. 6.3.2 Slabs In general, slab-on-grade floors (excluding those subjected to heavy tmck or forklift loading) should have a minimum thickness of 5 inches and be reinforced with No. 4 rebars 18 inches on center (each way) placed at mid- height in the slab. If heavy vehicle or equipment loading is proposed for the slabs, greater thickness and increased reinforcing may be required. In addition, interior slab-on-grade floors for the training tower and bum props stmctures may be subjected to a variety of unknown loading and environmental conditions, such as, heat and potentially chemicals that need to be evaluated by designers. Slabs should also have crack joints at spacings designed by the stmctural engineer. Columns should be stmcturally isolated from slabs. We emphasize 4 -22- Leighton 602256-001 that it is the responsibility of the contractor to ensure that the slab reinforcement is placed at slab mid-height. Interior floor slabs should be underlain by a 2-inch layer of clean sand (sand equivalent greater than 30), underlain by a 10-mil (or heavier) moisture barrier (visqueen), which is in tum is underlain by 2 inches of clean sand. All penetrations through the moisture barrier and laps should be sealed. All slabs should be constmcted with a reinforced thickened edge. A base coefficient of friction should not be applied to slab-on-grade where the visqueen is present. Our experience indicates that use of additional reinforcement in slabs and foundations can generally reduce the potential for drying and shrinkage cracking. However, some cracking should be expected as the concrete cures. Minor cracking is considered normal; however, it is often aggravated by a high water content, high concrete temperature at the time of placement, small nominal aggregate size, and rapid moisture loss due to hot, dry, and/or windy weather conditions during placement and curing. Cracking due to temperature and moisture fluctuations can also be expected. The use of low slump/water content concrete can reduce the potential for shrinkage cracking. Moisture barriers can retard, but not eliminate, vapor migration from the underlying soils up through the slab. We recommend that the floor coverings contractor test the moisture vapor flux rate through the slab prior to attempting the application of moisture-sensitive floor coverings. "Breathable" floor coverings or special slab sealants should be considered if vapor flux rates are high. Slip sheets should be considered if crack-sensitive floor coverings are planned on the slab. 6.3.3 Settlement The recommended allowable-bearing capacity is based on a maximum total and differential settlement of 3/4 inch and 1/2 inch, respectively. Since settlements are in part a function of footing size and contact bearing pressures, some differential settlement can be expected between adjacent columns or walls where a large differential loading condition exists. However for most cases, differential settlements are considered unlikely to exceed 1/2 inch and should generally be less than 1/4 inch. With increased footing depth/width ratios, differential settlement should be less. These values may be increased by one- third for short-term wind or seismic loads. 4 -23- Leighton 602256-001 6.3.4 Lateral Pressures Lateral loads may be resisted by assuming a passive pressure of 300 psf per foot of depth and coefficient of friction of 0.30 between concrete and soil. The lateral resistance may be taken as the sum of the passive and frictional resistance, provided the passive resistance does not exceed two-thirds of the total resistance. For design purposes, the recommended equivalent fluid pressure in each case for walls founded above the static ground water table (with level backfill) and backfilled with onsite or import soils of very low to low expansion potential (Expansion Index less than 50 per ASTM Test Method 4829) is shown on below. Table 3 Static Equivalent Fluid Weight (pcf) Condition Level 2:1 Slope Active 40 60 At-Rest 55 75 Passive 300 (Maximum of 3 ksf) The above values assume free-draining conditions. If conditions other than these covered herein are anticipated, the equivalent fluid pressure values should be provided on an individual case basis by the geotechnical engineer. Constmction traffic, compaction equipment, heavy equipment and vehicular traffic should be kept a minimum distance of 5 feet or retaining wall height, whichever is greater, from the retaining wall unless these surcharges are utilized in the design of the retaining walls. A surcharge load for a restrained or unrestrained wall resulting from automobile traffic may be assumed to be equivalent to a uniform lateral pressure of 75 psf which is in addition to the equivalent fluid pressure given above. For other uniform surcharge loads, a uniform lateral pressure equal to 0.35q should be applied to the wall (where q is the surcharge pressure in psf). All retaining wall stmctures should be provided with appropriate drainage and waterproofing. Wall drainage should be designed in accordance with the minimum recommendations shown on Figure 5. This may require special consideration with regard to providing adequate outlet for the drainage of the below grade parking stmcture. Wall backfill should be compacted by mechanical methods to at least 90 percent relative -24-4 Leighton 602256-001 m compaction (based on ASTM Test Method D1557) and at least 2 percent over the optimum moisture content. Wall footing design and setbacks should be performed in accordance with the previous foundation design recommendations and reinforced in accordance with stmctural considerations. Soil resistance developed against lateral stmctural movement can be obtained from the passive pressure value provided above. If wall rotation (A/H) is smaller than 0.04, a factor of safety of 2.5 should be used for the passive resistance. The upper 1 foot of passive resistance should be neglected unless the soil is confined by pavement or slab. m 6.4 Preliminary Pavement Design The appropriate pavement section will depend on the type of subgrade soil, shear strength, traffic load, and planned pavement life. Since an evaluation of the actual subgrade soils cannot be made at this tune, we have used an R-value of 5 and Traffic Indices (TI) of 5, 6, and 7. The range of pavement sections presented on Table 4 is to be used for preliminary planning purposes only. Final pavement designs should be completed in accordance with the City of Carlsbad design criteria after R-value tests have been performed on actual subgrade materials. Table 4 Preliminary Asphalt Pavement Designs Traffic Index Preliminary Pavement Section 5 3 inches AC over 10 inches Class 2 Aggregate Base 6 4 inches AC over 12 inches Class 2 Aggregate Base 7 4 inches AC over 16 inches Class 2 Aggregate Base Asphalt Concrete (AC) and Class 2 aggregate base should conform to and be placed in accordance with the latest revision of Califomia Department of Transportation Standard Specifications. Prior to placing the pavement section, the subgrade soils should have a relative compaction of at least 95 percent to a minimum depth of 12 inches (based on ASTM Test Method D1557). Aggregate Base should be compacted to a minimum of 95 percent relative compaction (based on ASTM Test Method D1557) prior to placement of the AC. Concrete pavement areas subjected to fire tmck traffic loading and heavy concentrated loads, such as, the areas surrounding the training tower and bum prop stmctures, require special consideration. We recommend a minimum section of 8 inches of Portland cement concrete (PCC) over 4 inches of Class 2 aggregate base. The PCC pavement section should be provided with appropriate crack-control joints as designed by the project stmctural -25-4 Leighton 602256-001 engineer. If sawcuts are used, they should be a minimum depth of V4 the slab thickness and made within 8 hours of concrete placement. We recommend that PCC pavement utilize a concrete mix design with a minimum 28-day strength of 3,250 psi. The upper 12 inches of subgrade soils should be compacted to at least 95 percent relative compaction based on ASTM Test Method D1557 prior to placement of aggregate base. The aggregate base layer should be compacted to at least 95 percent relative compaction as determmed by ASTM Test Method Dl557. PCC and Class 2 base materials should conform to and be placed in accordance with the latest revision of the Califomia Department of Transportation Standard Specifications (Caltrans) and American Concrete Institute (ACI) codes. 6.5 Construction Observation and Testing and Plan Review The geotechnical consultant should perform constmction observation and testing during the fine, and post grading operations, future excavations and foundation or retaining wall constmction at the site. Additionally, footing excavations should be observed and moisture determination tests of the slab subgrade soils should be performed by the geotechnical consultant prior to the pouring of concrete. Foundation design plans should also be reviewed by the geotechnical consultant prior to excavations. Hi 4 -26- Leighton 602256-001 7.0 LIMFTATIONS The conclusions and recommendations presented in this report are based in part upon data that were obtained from a limited number of observations, site visits, excavations, samples, and tests. Such information is by necessity incomplete. The nature of many sites is such that differing m geotechnical or geological conditions can occur within small distances and under varying climatic conditions. Changes in subsurface conditions can and do occur over time. Therefore, the » findings, conclusions, and recommendations presented in this report can be relied upon only if m Leighton has the opportunity to observe the subsurface conditions during grading and constmction of the project, in order to confirm that our preliminary findings are representative • for the site. ii 4 -27- Leighton I I I I SCALE LEGEND PtRiMfTl.R SECURITY WALL/TNCf: LI N E 8 , APPROXIMATE LOCATION OF SEISMIC LINES 1 (LEIGHTON, 2001) APPROXIMATE LOCATION OF TRENCH I ^ I EXPLORATION (LEIGHTON, 2001) LXISTING SPLCIMLN TREES TO REMAIN \ \ I 60 APPROXIMATE BORING LOCATION, DEPTH OF FILL (IN FEET), TOTAL DEPTH OF BORING (IN FEET) ARTIFICIAL FILL NON-STRUCTURAL (GEOCON, 198S) LUSARDI FORMATION, (CIRCLED WHERE BURIED) 120 FEET FIGURE 2 GEOTECHNICAL MAP CARLSBAD FIRST RESPONDER'S JOINT-USE TRAINING FACILITY CITY OF CARLSBAD, CALIFORNIA Leighton Proj: 60225&O01 Scale: 1"=30' Date: 7/08 Leighton Eng/Geol: WDO/RKW Drafted By: MAM CP By: BQT Leighton P:\DRAFTING«02256\0011OF_2«W-07-08\PLATE1-CEOMW>.DWG(07-21-0ei0:314MM| PWtoii by: mmuphy CONCEPTUAL SITE PLAN 1 P99 SLICEAND F^'E'DIPT -^^'^""^ ^^^^^ RESPONDERS TRAINING FACILITY SCALE: 1" = 30'-0" 1107570 May, 2008 1 rrmdesigngrouplll creating environments people enjoy Appendix A 602256-001 APPENDIX A REFERENCES Bartlett, S.F. and Youd, T.L., 1995, Empirical Prediction of Liquefaction-Induced Lateral Spread, Joumal of Geotechnical Engineering, Vol. 121, No. 4 , April 1995. Blake, 2000, EQFAULT, Version 3.0. Califomia Geologic Survey (CGS), 2003), Probabilistic Seismic Hazard Analysis Map, June 2003. Califomia Building Standards Commission (CBSC), 2007, Califomia Building Code (CBC). Geocon, Inc., 1982, Soil Investigation and Geologic Reconnaissance for Civic Operations Center, Carlsbad, Califomia, File No. P-2751-J01, dated June 14, 1982. , 1984, Updated Geotechnical Investigation for City of Carlsbad Safety Center, Carlsbad, Califomia, File No. D-2751-J02, dated September 12, 1984. , 1985, Final Report of Testing and Observation Services During Mass Grading Operations for Carlsbad Safety Center, Carlsbad, Califomia, File No. D-2751-J03, dated June 17, 1985. Hart, 1997, Fault Rupture Hazard Zones in Califomia, Alquist-Priolo Special Studies Zones Act of 1972 with Index to Special Study Zone Maps, Department of Conservation, Division of Mines and Geology, Special Publication 42, revised 1997. Hannan, D., 1975, Faulting in the Oceanside, Carlsbad and Vista Areas, Northem San Diego County, Califomia in Ross, A. and Dowlens, R.J., eds.. Studies on the Geology of Camp Pendleton and Westem San Diego County, Califomia: San Diego Association of Geologists, pp. 56-59. Ishihara, K., and Yoshimine, M., 1992, Evaluation of Settlements in Sand Deposits Following Liquefaction during Earthquakes, Soils and Foundations, Vol. 32, No. 1, pp: 173- 188. Leighton and Associates, Inc., 1988, As-Graded Report of Rough Grading Operations, City of Carlsbad Fire Station No. 5, Carlsbad Safety Center, Carlsbad, Califomia, Project No. 8871838-04, dated September 8, 1988. A-1 602256-001 APPENDIX A (Continued) , 2001, Update Geotechnical Investigation, Proposed Carlsbad Public Works Center Facility Expansion, Orion Way and Orion Street, Carlsbad, Califomia, Project No. 040448-001, dated September 4, 2001. RRM Design Group, 2008, Conceptual Site Development Plan, Joint First Responders Training Facility, dated May 2008. Youd, T.L., 1993, Liquefaction-Induced Lateral Spread Displacement, NCEL Tech. Note 1862, Naval Civil Engineering Laboratory, Port Hueneme, Califomia. Youd, T.L., Hanson CM., and Bartlett, S.F., 1999, Revised MLR Equations for Predicting Lateral Spread Displacement, Proceedings of the 7^ U.S.-Japan Workshop on Earthquake Resistant Design of Lifeline Facilities and Countermeasures Against Soil Liquefaction, November 19, 1999, pp. 99-114. A-2 Appendix B GEOTECHNICAL BORING LOG KEY Date Project KEY TO BORING LOG GRAPHICS Drilling Co. Hole Diameter Elevation Top of Elevation ' Sheet _! of _\_ Project No. _^ Type of Rig Drive Weight Location Drop is. UJ a* O tL (A 0) •o 3 O z o Q. E re (0 (AO CQoi Q. (A 0) O oa Q 0,0- oc SO O (0— DESCRIPTION Logged By Sampled By (A Q> o a >» H mill 10- 15- 57 _ 20- 25- 30- 1^ B-l C-1 G-1 P R-1 SH-1 S-1 I Asphaltic concrete Portland cement concrete CL CH Inorganic clay of low to medium plasticity; gravelly clay; sandy clay; silty clay; lean clay OL ML Inorganic silt; clayey silt with low plasticity MH Inorganic silt; diatomaceous fine sandy or silty soils; elastic silt ML-CL Clayey silt to silty clay GW Well-graded gravel; gravel-sand mixture, little or no fines GP TJM Poorly graded gravel; gravel-sand mixture, little or no fines "GC" Clayey gravel; gravel-sand-clay mixture Well-graded sand; gravelly sand, little or no fines Poorly graded sand; gravelly sand, little or no fines SM Silty sand; poorly graded sand-silt mixture SC Bedrock Ground water encountered at time of drilling Bulk Sample Core Sample Grab Sample Modified Califomia Sampler (3" CD., 2.5 LD.) Shelby Tube Sampler (3" O.D.) Standard Penetration Test SPT (Sampler (2" O.D., 1.4" I.D.) SAMPLE TYPES: S SPUT SPOON R RING SAMPLE B BULX SAMPLE T TUBE SAMPLE G GRAB SAMPLE SH SHELBY TUBE TYPE OF TESTS: DS DIRECT SHEAR MD MAXIMUM DENSITY CN CONSOUDATION CR CORROSION SA SIEVE ANALYSIS AT ATTERBURG UMITS El EXPANSION INDEX RV R-VALUE 4 LEIGHTON GEOTECHNICAL BORING LOG B-1 Date 6-30-08 Project Carlsbad/JFRTF Drilling Co. Baja Excavation Hole Diameter 8 in. Elevation Top of Elevation 355' Drive Weight Location Sheet 1 Of _± Project No. Type of Rig 602256-001 CME-75 140 pound hammer See Geotechnical Map Drop 30" 111 355 350 345- 340 335 330 10- 15- 20— 25- 325-' 30- •5o» 2-1 o (A 0) T3 B 5 < a E re (0 B-l 0'-5' R-1 (AO ^O Q. I 50/6" R-2 (A 0) u .PC (A® Oc SO O 107.7 I 50/4" 9.1 5": —CO OD "SM" SP SM A; Logged By Sampled By DESCRIPTION BP BP Grass surface ARITFICIAL FILL (^U'-2': Fme to medium grained silty SAND: Dark brown, moist @ 2': Light brown, damp LUSARDI FORMATION @ 5': Fine to coarse grained SAND: Orangish brown, damp, very dense, cemented conglomerate, sli^tly undisturbed ^ 10': Difficult drilling me to coarse grained silty SAND: Light brown to organish brown, damp, very dense, cemented conglomerate, little recovery ^Refusal at 11 feet Total Depth = 11 Feet No ground water encountered at time of drilling Backfilled on 6/30/08 O 0) SAMPLE TYPES: S SPLIT SPOON R RING SAMPLE B BULK SAMPLE T TUBE SAMPLE G GRAB SAMPLE SH SHELBY TUBE TYPE OF TESTS: DS DIRECT SHEAR MD MAXIMUM DENSITY CN CONSOUDATION CR CORROSION HC HYDRAULIC CONDUCTIVITY AT ATTERBURG UMITS El EXPANSION INDEX RV R-VALUE 4 LEIGHTON GEOTECHNICAL BORING LOG B-2 Date 6-30-08 Project Carlsbad/JFRTF Drilling Co. Baja Excavation Hole Diameter 8 in. Sheet 1 Of _± Project No. Type Of Rig 602256-001 CME-75 Elevation Top of Elevation 355' Drive Weight Location 140 pound hammer See Geotechnical Map Drop 30" re I-•SO* S-o O (A O •a B o z o a E re CO (AO SO 0. (A Cif. a>u QQ. .PC (A© Oc 20 o OD DESCRIPTION Logged By Sampled By BP BP (A 0> O 355 350 5— 345 10— 340 15- B-1 0'-5' R-1 Grass surface ARTOlCIALraX @U': Fine to medium grained silty SAND: Ligjit brown, moist I 50/4" 100.7 10.: LUSARDI FORMATION @ 5': Fine to coarse grained silty SAND: Light brown to orangish brown, moist, very dense, conglomerate, slightly disturbed R-2 I 50/4" @ 10': Damp, little recovery R-3 B-2 15' I 50/3" 335-20— 330-25- 325-' 30 @ 15': Little recovery A@19': Hard drilling, refijsal Total Depth = 19 Feet No ground water encountered at time of drillins Backfill on 6/30/08 SAMPLE TYPES: S SPUTSPOON R RING SAMPLE B BULK SAMPLE T TUBE SAMPLE G GRAB SAMPLE SH SHELBY TUBE TYPE OF TESTS: DS DIRECT SHEAR MD MAXIMUM DENSITY CN CONSOUDATION CR CORROSION HC HYDRAUUC CONDUCTIVITY AT ATTERBURG UMITS El EXPANSION INDEX RV R-VALUE 4 LEIGHTON GEOTECHNICAL BORING LOG B-S Date 6-30-08 Project Carlsbad/JFRTF Drilling Co. Baja Excavation Sheet 1 Of _± Project No. Type of Rig 602256-001 CME-75 Hole Diameter 8 in. Elevation Top of Elevation 366' Drive Weight Location 140 pound hammer Drop 30" See Geotechnical Map o.^ reo) UJ u. •5o» S-o (A 0> X3 B e < 0) Q. E re (0 CQa> Q. (A CM- 0)0 oa 0,6^ Be Oc SO <A^ DESCRIPTION Logged By Sampled By BP BP i2 (A 0) a 365 360 10- 355- 15- 350 20- B-1 0'-5' "SM" 50/4" Grass surface ARTOlCIALraX @0': Fine to medium grained silty SAND: Dark brown, moist, some rock/cobbles/difficult drilling 2 to 4 feet ;5': No sample recovery CR R-1 I 50/1" R-2 B-2 15' R-3 345 25— 340 30- @ 10': Fine to medium grained silty SAND: Dark brown, moist, very (fense,_disti£bed LUSARDI FORMATION 50/5" 70/6" SP @ 15': Fine to coarse grained silty SAND with cobbles and graveL up to 1/2 inches in diameter, subangular, light brown to orgamsh brown, damp, very dense, disturbed - difficult drilling at 17 to 18 feet ^ 20': Fine to coarse grained SAND: Light brown to orangish brown, damp, very dense, cemented conglomerate ^21': Difficult drilling ARefiisal at 22 feet /- Total Depth = 22 feet No ground water encountered at time of drilling Backfilled on 6/30/08 SAMPLE TYPES: S SPUT SPOON R RING SAMPLE B BULK SAMPLE T TUBE SAMPLE G GRAB SAMPLE SH SHELBY TUBE TYPE OF TESTS: DS DIRECT SHEAR MD MAXIMUM DENSITY CN CONSOUDATION CR CORROSION HC HYDRAULIC CONDUCTIVITY AT ATTERBURG UMITS El EXPANSION INDEX RV R-VALUE 4 LEIGHTON GEOTECHNICAL BORING LOG B-4 Date 6-30-08 Project Carlsbad/JFRTF Drilling Co. Baja Excavatio Sheet 1 of 1 Project No. Type of Rig 602256-001 CME-75 Hole Diameter 8 in. Elevation Top of Elevation 364' Drive Weight Location 140 pound hammer See Geotechnical Map Drop 30" 1^ req, I"- UJ I2 tL -So> S-o O (A •o B 5 < a E re (0 (AO $o ou- — k. QQO) Q. (A C<«- 0)0 QQ. >» .PC (A® OC SO O (A^ "ozi Logged By Sampled By DESCRIPTION BP BP (A o §: 360 5— 355- 10- 350- 15— 345 20- 340 25- 335 30- B-1 0'-5' R-1 "srar I 39 130.4 10.0 Grass surface ARTIFICIAL FILL @0': Fine to medium grained silty SAND: Dark brown, moist @ 3': Fine to medium grained silty SAND: Light brown, damp with cobbles, up to 1/2 inches in diameter, subangular @ 5': No recovery, 1st resample, rock in shoe, 2nd time, no sample, 3rd - recovery Fine to coarse grained silty SAND: Dark brown to reddish brown, damp, medium dense R-2 I 50/3" SP B-2 15 B-3 20 R-3 LUSARDI FORMATION @ 10': Fine to coarse grained SAND: Light brown to organish brown, cemented conglomerate, disturbed, damp, very dense 50/2" @ 15': No recovery 50/2" SM @ 20': Fine to medium grained silty SAND: Brown, damp, very dense, fi-om shoe and disturbed sample I 50/4" 106.1 8.7 @ 25': Fine to coarse grained silty SAND: Light brovm to reddish brown with cobbles up to 1/2 mches in diameter, subangular, cemented conglomerate ^(a), 28': Hard drilling and refiisal, no sample recovery Total Depth = 28 Feet No ground water enc RaflffillffH on 6/3n/n« No ground water encountered at time of drilling DS SAMPLE TYPES: S SPLIT SPOON R RING SAMPLE B BULK SAMPLE T TUBE SAMPLE G GRAB SAMPLE SH SHELBY TUBE TYPE OF TESTS: DS DIRECT SHEAR MD MAXIMUM DENSITY CN CONSOUDATION CR CORROSION HC HYDRAUUC CONDUCTIVITY AT ATTERBURG UMITS El EXPANSION INDEX RV R-VALUE LEIGHTON GEOTECHNICAL BORING LOG B-5 Date 7-1-08 Project Carlsbad/JFRTF Drilling Co. Baja Excavation Hole Diameter 8 in. Elevation Top of Elevation 356' Drive Weight Location Sheet 1 of Project No. Type of Rig 602256-001 CME-75 140 pound hammer See Geotechnical Map Drop 30" lU 1-2 O •SO) s-o tL (A 0) B I Q. E re (0 (AO ^O O"^ £Qo> OL <A CM- QQ. >» 0)0^ .PC (AO) Oc SO o (A-^ O . DESCRIPTION Logged By Sampled By BP BP o 355 350 10- 345 15- 340 20- 335 R-1 B-l 0'-5' "SM" I 50/4" 103.4 6.0 R-2 I 50/6" I R-3 I 50/1" R-4 I 50/5" I Grass surface ARTIFICIAL FILL (o^U': Fme to medium grained silty SAND: Dark brown, moist LUSARDI FORMATION @ 5': Fine to coarse grained silty SAND: Light brown to organish brown, damp, very dense conglomerate 25- 330- 30- @ 10': Disturbed sample @ 15': No recovery ! 20': Difficult drilling, disturbed sample •\Refiisal at 24 feet Total Depth = 24 feet below ground surface No ground water encountered at time of drilling Backfilled with bentonite on 7/1/08 SAMPLE TYPES: S SPUTSPOON R RING SAMPLE B BULK SAMPLE T TUBE SAMPLE G GRAB SAMPLE SH SHELBY TUBE TYPE OF TESTS: DS DIRECT SHEAR MD MAXIMUM DENSITY CN CONSOLIDATION CR CORROSION HC HYDRAULIC CONDUCTIVITY AT ATTERBURG LIMITS El EXPANSION INDEX RV R-VALUE 4 LEIGHTON GEOTECHNICAL BORING LOG B-6 Date 7-1-08 Project Carlsbad/JFRTF Drilling Co. Baja Excavation Sheet 1 of 1 Project No. Type of Rig 602256-001 CME-75 Hole Diameter 8 in. Elevation Top of Elevation 351' Drive Weight Location 140 pound hammer Drop 30" See Geotechnical Map c O- UJ Is tL •5o> S-o o (A 0) •o 5 S < 0) a E re V) CQa> Q. (A C4. 0) u QQ. >« .PC (AO) OC SO o o . OD Logged By Sampled By DESCRIPTION BP BP (A 0) I->»- o 350 345 10- 340 15- 335-1 -I 20- 330 25- 325 Dirt/gravel surface ARTIFICIAL FILL @0': Fine to coarse grained silty SAND: Dark brown, wet, medium dense R-1 B-l 0'-5' I 42 110.0 11.7 ! 7': Change to light brown, moist, in cuttings I R-2 • 50/2" LUSARDI FORMATION @ 10': Fine to coarse grained silty SAND: Light brown to organish brown, very dense, damp R-3 I 50/1" 15': Conglomerate, disturbed 30- 50/1" @ 25': Fine to coarse grained silty SAND: Light brown to organish brown, very dense, damp, conglomerate, small amount of sample fi*om shoe ^ 26': Refusal, difficult drilling 1 otal Depth = 26 Feet No ground water encountered at time of drilling Backfilled with bentonite on 7/1/08 / SAMPLE TYPES: S SPLIT SPOON R RING SAMPLE B BULK SAMPLE T TUBE SAMPLE G GRAB SAMPLE SH SHELBY TUBE TYPE OF TESTS: DS DIRECT SHEAR MD MAXIMUM DENSITY CN CONSOUDATION CR CORROSION HC HYDRAUUC CONDUCTIVITY AT ATTERBURG UMITS El EXPANSION INDEX RV R-VALUE 4 LEIGHTON GEOTECHNICAL BORING LOG B-7 Date 7-1-08 Project Carlsbad/JFRTF Drilling Co. Baja Excavation Hole Diameter 8 in. Elevation Top of Elevation 352' Drive Weight Location Sheet 1 of 1 Project No. Type of Rig 602256-001 CME-75 140 pound hammer See Geotechnical Map Drop 30" 1% reo) UJ I- tL s-o 2_i o (A O •a B S < o z o> Q. E re V) a. (A Ci*. ou QQ. >« .PC <««) Oc so o (A-r OD CO— DESCRIPTION Logged By Sampled By BP BP (A a> H-<^ O o CL >^ I- 350 345 10- 340 15—: 335 20- 330 25— 325 30- B-1 0'-5' R-1 "SM" Grass surface ARTIFICIAL FELL @0': Fine to medium silty SAND: Medium brown, damp to moist I 36 122.6 10.5 @ 5': Fine to coarse silty SAND: Dark reddish brown, moist, medium dense 17': Cuttings change to light brown R-2 I 50/3" LUSARDI FORMAITON @ 10': Fine to coarse grained silty SAND: Light brown to orangish brown, damp, very dense, conglomerate R-3 I 50/6" @ 15': Light brown, organish brown to dark brown R-4 B-2 20' I 50/2" 120': Fine to coarse silty SAND: Light brown to organish brown, damp, very dense, conglomerate -\@ 23': Refiisal, difficult drilling ' Total Depth = 23 Feet No ground water encountered at time of drilling Backfilled with bentonite on 7/1/08 SAMPLE TYPES: S SPUTSPOON R RING SAMPLE B BULK SAMPLE T TUBE SAMPLE G GRAB SAMPLE SH SHELBY TUBE TYPE OF TESTS: DS DIRECT SHEAR MD MAXIMUM DENSITY CN CONSOUDATION CR CORROSION HC HYDRAULIC CONDUCTIVITY AT ATTERBURG LIMITS El EXPANSION INDEX RV R-VALUE LEIGHTON GEOTECHNICAL BORING LOG B-8 Date 7-1-08 Sheet 1 of Project Carlsbad/JFRTF Drilling Co. Baja Excavation Project No. Type of Rig 602256-001 CME-75 Hole Diameter 8 in. Elevation Top of Elevation 354' Drive Weight Location 140 pound hammer Drop 30" See Geotechnical Map c o*- reo) UJ I-S-o O (A <D •D B i 0) "5. E re (0 03 a> a. (A Ci*. .PC oc SO O (A^ -d o . OZ) Logged By Sampled By DESCRIPTION BP BP (0 0) 0) a >» I- 350 5— 345 10— 340 15- 335 20- 330 25— 325 30- B-1 0'-5' R-1 I 50/5" I R-2 • 50/5" I R-3 I 50/3" I R-4 • 50/4" R-5 I 50/3" B-2 25' Grass at surface ARTIFICIAL FILL @0': Fine to medium grained silty SAND: Dark brown, moist @ 2': Light brown, damp LUSARDI FORMATION 15': Fine to medium grained silty SAND: Light brown, damp, very dense @ 10': Fine to coarse grained silty SAND: Light brown to orangish brown, damp, very dense, conglomerate, disturbed, shoe sample on top @ 15': Fine to mediiun grained silty SAND: Light brown to organish brown, damp, very dense, less coarse than previous ;20': Cemented @25': Rock in sample SAMPLE TYPES: S SPLIT SPOON R RING SAMPLE B BULK SAMPLE T TUBE SAMPLE G GRAB SAMPLE SH SHELBY TUBE TYPE OF TESTS: DS DIRECT SHEAR MD MAXIMUM DENSITY CN CONSOUDATION CR CORROSION HC HYDRAULIC CONDUCTIVITY AT ATTERBURG UMITS El EXPANSION INDEX RV R-VALUE 4 LEIGHTON GEOTECHNICAL BORING LOG B-8 Date 7-1-08 Sheet 2 of Project Carlsbad/JFRTF Drilling Co. Baja Excavation Project No. Type of Rig 602256-001 CME-75 Hole Diameter 8 in. Elevation Top of Elevation 354' Drive Weight Location 140 pound hammer Drop ^ See Geotechnical Map c o*- reo) UJ tL •So» S-o o (A •u B e < o z o a. E re (0 lO ;o a. (A CM-0) o >« .PC <A0> Oc SO o -d OD Logged By Sampled By DESCRIPTION BP BP (A o 0) Q. I- 30-1 320 35— 315 40- R-6 50/4" SM 310 45— 305 50— 300 55— 295 60- @ 30': Fine to medium grained silty SAND: Dark brown to orangish brown, damp, very dense @ 35': No sample, drilled to 40 feet @38': Difficult drilling 50/0" ANO recovery, refiisal Total Depth = 40 Feet No ground water encountered at time of drilling Backfilled with bentonite on 7/1/08 SAMPLE TYPES: S SPLIT SPOON R RING SAMPLE B BULK SAMPLE T TUBE SAMPLE G GRAB SAMPLE SH SHELBY TUBE TYPE OF TESTS: DS DIRECT SHEAR MD MAXIMUM DENSITY CN CONSOUDATION CR CORROSION HC HYDRAUUC CONDUCTIVITY AT ATTERBURG UMITS El EXPANSION INDEX RV R-VALUE 4 LEIGHTON GEOTECHNICAL BORING LOG B-9 Date 7-1-08 Project Carlsbad/JFRTF Drilling Co. Baja Excavation Sheet 1 of _± Project No. Type of Rig 602256-001 CME-75 Hole Diameter 8 in. Elevation Top of Elevation 352' Drive Weight Location 140 pound hammer Drop 30" See Geotechnical Map reo) I"" LU |2 Ii. S-o (A 0) •o B I a E re CO CL (A C«*-0) O .PC (A® Oc SO o (A^ -d o • _eo OZ) CO—' Logged By Sampled By DESCRIPTION BP BP (A (A 0> I- O 0> a. >^ I- 350 Unpaved dirt surface, loose at surface ARTIFICIAL FELL @0': tme to medium grained silty SAND: Light brown, damp, some rocks encountered during drilling 0 to 3 feet : 3': Cuttings change to dark brown R-1 B-l 0'-5' 50/6" 104.4 7.9 345 10- 340 15- 335- 20- 330 25— 325 30- 1 LUSARDI FORMATION @5': Fine to coarse grained silty SAND: Light brown to organish brown to dark brown, damp, very dense conglomerate l otal Depth = 5 Feet No ground water encountered at time of drilling Backfilled with bentonite on 7/1/08 HC SAMPLE TYPES: S SPLIT SPOON R RING SAMPLE B BULK SAMPLE T TUBE SAMPLE G GRAB SAMPLE SH SHELBY TUBE TYPE OF TESTS: DS DIRECT SHEAR MD MAXIMUM DENSITY CN CONSOUDATION CR CORROSION HC HYDRAULIC CONDUCTIVITY AT ATTERBURG UMITS El EXPANSION INDEX RV R-VALUE 4 LEIGHTON Exploration Trenches Logs for T-3 an T-4 (Leighton, 2001) LOG OF TRENCH: 1=1 Project Name: Gill's/Carljjbad PWC T npcrpH Hy SW Project Number! 040448-001 Fl'^vatinn-ENGINEERING PROPERTIES Equipment: rATlinFRnrVhnr Location/Grid: S*^*^n*»,^wl,«iral lUap Equipment: rATlinFRnrVhnr Location/Grid: S*^*^n*»,^wl,«iral lUap GEOLOGIC ATTITUDES DATE: 5/25/01 DESCRIPTION: GEOLOGIC UNIT uses Sample No. Moisture (%) Density (vcf) ARTIFICL\L FILL-nonstnictural Afn Topsoil/ Qcol 3 @7.8' v >^ A @ 0'-4.5': Clayey silty medium to coarse SAND with few fine gravels, cobbles and boulders: light to dark brown and gray, moist, medium dense TOPSOIL/COLLUVIUM Afn Topsoil/ Qcol SM- SC 3 @7.8' B @ 4.5'-6': SAND/SILT: dark gray-brown, moist, loose; with scattered organic debris (odor) and few rounded gravel C @ 6'-6.3': Silty SAND: chocolate brown, moist, loose; few organic debris; micaceous @ 6.3'-7': Sandy CLAY: gray/brown, moist, firm to stiff LUSARDI FORMATION Afn Topsoil/ Qcol SM/ ML SM SC E @ 7'-8': Medium to coarse SANDSTONE CONGLOMERATE, weathered granitic gravel, cobbles and boulders in a medium to coarse sandstone matrix: light brown, gray-brown and brown, orange/red, damp, very dense Kl GP GRAPfflCAL REPRESENTATION: SCALE: r*=5' SURFACE SLOPE: 5° to E TREND: N25W Total Depth = 8 Feet No Ground Water Encountered Backfilled: 5/25/01 (uncompacted) LOG OF TRENCH: T-4 Project Name: Gillis/CarlshaH Pwr Project Number: Equipment: 04044R-001 Logged by: Eleyation:_ CATIIOF RRrkhoe GEOLOGIC ATTITUDES Location/Grid: r^»t^^hn?>'*' DATE: 5/25/01 DESCRIPTION: ARTIFICIAL FILL-nonstnictiiral ~ " A @ 0'-2.5': Clayey silty medium to coarse SAND with scattered gravel and cobble: brown to light gray-brown, moist, mediimi dense TOPSOIL/COLLLTVIUM B @ 2.5'-3': Silty medium to coarse SAND: dark gray, damp, loose; scattered organic debris (odors) C @ 3'-4': Silty medium to coarse SAND: chocolate brown, damp, loose: micaceous rare; organic debris LUSARDI FORMATION D @ 4'-5': Medium to coarse SANDSTONE CONGLOMERATE, weathered granitic gravel, cobbles and boulders in a medium to coarse sandstone matrix: light brown, gray-brown and brown, orange/red, damp, very dense GEOLOGIC UNIT Afn Topsoil/ Qcol Kl ENGINEERING PROPERTIES uses SM- SC SM SM Gp Sample No. 4 4-5' Moisture Density GRAPfflCAL REPRESENTATION: SCALE: 1=2* SURFACE SLOPE: 0° TREND: NlOE Appendix C 602256-001 APPENDD( C Laboratory Testing Procedures and Test Results Direct Shear Test: A direct shear test was performed on a selected remolded sample which was soaked for a minimum of 24 hours under a surcharge equal to the applied normal force during testing. After transfer of the sample to the shear box and reloading of the sample, the pore pressures set up in the sample (due to the transfer) were allowed to dissipate for a period of approximately 1 hour prior to application of shearing force. The sample was tested under various normal loads utilizing a motor-driven, strain-controlled, direct-shear testing apparatus at a strain rate of 0.05 inches per minute. After a shear strain of 0.2 inches, the motor was stopped and the sample was allowed to "relax" for approximately 15 minutes. The stress drop during the relaxation period was recorded. It is anticipated that, in a majority of samples tested, the 15 minutes relaxing of the samples is sufficient to allow dissipation of pore pressures that may have set up in the samples due to shearing. The drained peak strength was estimated by deducting the shear force reduction during the relaxation period from the peak shear values. The shear values at the end of shearing are considered to be ultimate values and are shown in parenthesis. Sample Location Sample Description Test Type Friction Angle (degrees) Apparent Cohesion (psf) B-4, @ 0-5 Feet Brown Clayey to Silty Sand Remolded to 90% 27 (27) 300(150) Maximum Densitv Tests: The maximum dry density and optimum moisture content of typical materials were determined in accordance with ASTM Test Method D1557. The results of these tests are presented in the attached data. Sample Location Sample Description Maximum Dry Density (pcf) Optimum Moisture Content (%) B-4, @ 0-5 Feet Brown Clayey to Silty Sand (SC-SM) 131.0 8.0 B-9, @ 0-5 Feet Yellowish Brown Sand w/Clay (SP-SC) 133.5 7.5 C-1 602256-001 APPENDIX C (Continued) Minimum Resistivity and pH Tests: Minimum resistivity and pH tests were performed in general accordance with Caltrans Test Method CT643 for Steel or CT532 for concrete and standard geochemical methods. The results are presented in the table below: Sample Location Sample Description pH Minimum Resistivity (ohms-cm) B-3 @ 0 - 5 Feet Brown Silty Sand (SM) 7.39 6,000 Chloride Content: Chloride content was tested in accordance with Caltrans Test Method CT422. The results are presented below: Sample Location Chloride Content, ppm Chloride Attack Potential* B-3 @ 0 - 5 Feet 84 Threshold Soluble Sulfates: The soluble sulfate contents of selected samples were determined by standard geochemical methods (Caltrans Test Method CT417). The test results are presented in the table below: Sample Location Sample Description Sulfate Content (%) Potential Degree of Sulfate Attack* B-3 @ 0 - 5 Feet Brown Silty Sand (SM) 0.018 Negligible Conference of Building Officials (ICBO, 1997). Moisture and Densitv Determination Tests: Moisture content and dry density determinations were performed on relatively undisturbed samples obtained from the test borings. The results of these tests are presented in the boring logs. Where applicable, only moisture content was detemiined from "undisturbed" or disturbed samples. C-2 602256-001 APPENDDC C (Continued) Hydraulic Conductivitv TASTM D5Q84^: Hydraulic conductivity tests are performed on selected undisturbed and remolded samples collected from the exploratory borings. These tests are performed in general accordance with the ASTM Test Method D5084. The samples are placed in the triaxial testing device and tested with a Falling Head Method. The table below reports the average hydraulic conductivity values for the samples. Sample Location Average Hydraulic Conductivity (cm/sec) B-9, (remolded - 90% RC) Sand w/clay(SP-SC) 0.000021 C-3 Appendix D Seismic Refraction Survey (Leighton, 2001) 215 So. Highway 101. Suite 203 P.O. Box 1152 Solana Beach. CA 92075 Telephone: (858) 481-8949 Facsimile: (858) 481-8998 Website: subsurfacesurveys.com August 29, 2001 Leighton and Associates 3934 Murphy Canyon Road, Suite B-205 San Diego, CA 92123 Project / Invoice Number: 01-335 Attn: Mike Jensen Re: Seismic Refraction Survey, Carlsbad, Califomia Introduction - This report presents the findings of a seismic refraction survey conducted over the gravel lot on the northeast corner and the baseball diamond on the southeast corner of Orion Way and Orion Street in Carisbad, Califomia (Fig. 1) on August 10*. 2001. The purpose of this survey was to evaluate the thickness of fill, alluvium/colluvium, and depth to bedrock. Instrumentation and Field Procedure - A total of 1816 lineal feet of data was collected along 8 survey lines. The seismic line locations were mariced in the field with paint and were detailed on a topographic map supplied by the client's representative (Fig. 2). The spread layouts were detemiined at the site, and were critically located to maximize useable infomiation. Seismic waves were initiated at the ends of each spread by striking an aluminum plate with a 20-pound sledge (Fig 3). Seismic arrivals were detected by a series of twenty-four geophones, and recorded with a Bison 9024 24 channel seismic system with DIFP, digital instantaneous floatirig point, capability. This automatically sets gains, balances channels, and sets other shooting paranr>eters, in real time. The materials at the site provide good transmission of seismic energy, and the records produced are of good quality. MethodoloQv - The refraction method uses first-anival times of refracted seismic waves to determine tiie thicknesses and seismic velocities of subsurfiace materials. Seismic waves generated at tiie surface are reflected and refiracted fifom boundaries separating materials of contrasting velocities, and are detected by a series of surface geophones. The tiavel times of the seismic waves are used in conjunction witii ttie shot-geophone distances to obtain tfiickness and velocity Infonnation, in ttiis case geophone spacing varied between five, ten, and twelve feet (line length depended on access and desired coverage) and shot points were conducted at either five or ten feet off each end of the line and between geophones 6 and 7,12 and 13, and 18 and 19. The line lengttis varied between 120 and 276 feet in lengtii and allowed for an approximate deptfi of investigation of approximately one third of the overall line length. CD CD BES lAL The seismic refraction technique requires that velocities increase with depth, which is usually the case. A layer having a velocity lower than that of the layer above will not be detectable by seismic refraction, and will lead to errors in the depth computations to any subsequent layers. The processing of tiie acquired data is computationally intense. A ray tradng computer program, SIPT2, is used to iteratively honor all detector infomiation to detemiine dip and irregularities in the refracting surfaces, and to be able to consider a large number of layers, where tfiey are developed. A picking program, with such features as zoom, filtering, time stretching, and separation of traces is also used. Rock Rippability Classification - In order to group the materials to be excavated in ternis of difficulty of excavation, Caterpillar has adopted a three-fold classification scheme, the independent variable , being seismic velocity. This classification is based on experience with similar rocks in various locals, and assumes multi or single shank D9N or equivalent equipment. The rocks are classified as follows: D9N Ripper Performance • Multi or Single Shank No. 9 Ripper Estimated by Seismic Wave Velocities Rippers Seismic Velocity o Meiers Per SecoMd > I0(>0 L Feel Per Second * tOOO 0 TOPSOIL CLAY GLACIAL TILL IGNEOUS ROCKS GRANITE BASALT TRAP ROCK SEDIMENTARY ROCKS SHALE SANDSTONE SILTSTONE CLAYSTONE CONGLOMERATE BRECCIA CALICHE LIMESTONE METAMORPHIC ROCKS SCHIST SLATE MINERALS 4 ORES COAL IRON ORE ^^^^^^^^ ^^^^^^^ RIPPABLE MARGINAL C NONRIPPABLE ^V^V^\^^^ Marginal npping refers to rocks in which it becomes difficult to achieve tootti penetration sharply reducing npping production. Local blasting may be necessary in order to maintain a desired ripping production rate. Non-rippable refers to rocks in which tfie use of heavy machinery is likely to cease being a cost-effective method of excavation, necessitating ttie use of explosives to maintain a desired excavation rate. We emphasize ttiat the cutoflis in ttiis classification scheme are approximate and ttiat rock characteristics, such as fracture spacing and orientation, play a major role in determining rock rippability. Findings - Example monitor records from Line 3 are presented in figure 4 to illustrate data quality for a typical fonvard, mid(X 3), and reverse shot sequence. The data recorded is displayed in time-distance plot format in order to complete layer assignments. The curves for the forward, mid(X 3), reverse, shots from Line 3 are displayed on the same graph (Fig. 5). After layers are identified, the redundant data provided over each spread, are input into the iterative, ray tracing modeling program. The resulting geologic stmcture sections for the eight lines are illustrated on Figures 6 through 13. Lines 1 through 3 of the seismic lines collected illustrate a three-layer case. These layers are interpreted to represent fill material overlying alluvium/colluvium/soil overiying bedrock. The velocities of the layers are also well defined: Layer Velocity (ft/sec) Material 1 1690-2149 Fill material 2 2826^177 Alluvium/Colluvium/Soil 3 4585-5807 Bedrock Lines 4 through 8 of the seismic lines collected illustrate a two-layer case. These layers are interpreted to represent fill material overiying bedrock. The velocities of the layers are also well defined: Layer Velocity (fl/sec) Material 1 1690-2149 Fill material 3 4585-5807 Bedrock Note: The measured seismic velocities represent average velocities of the subsurface materials, and significant local variations may be present at any level. Conclusions - The interpretation for the seismic lines collected agree well witti ttie results of ttie geotechnical trenching logs provided by the client witti respect to lateral limits detemiined for tiie fill and alluvium/colluvium. An exception to this was found for ttie baseball field portion of tiie survey area where geotechnical logs indicate a thin layer of alluvium/colluvium underiying engineered fill (suggesting a ttiree layer case). Seismic data for tills portion of the survey area suggests a two- layer case. This may be due to a lack of significant thickness and/or velocity contrast between the fill and alluvium/colluvium. It should also be noted ttiat undulations for refiractors presented in cross sectional view may be the result of lateral changes In velocity and are exaggerated due to choice of an expanded depth scale relative to ttie horizontal scale. All data acquired in tiiese surveys are in confidential file in ttiis office, and are available for review by your staff, or by us at your request, at any time. We appreciate tiie opportunity to participate in ttiis project. Please call, if there are questions. Patrick F. Lehrmann Gary W. Crosby, Ph.D., GP 960 Staff Geol/Geophysicist Senior Geol/Geophysidst Ht-ruk' ^tjOtt^fi %t* ,Pf;t0 0U» j.^ TIM »i>»N rl ,wKJrt -1 arm ••.ttmifa 9( urn* pot r* ten ZSt}«»<* * Off ' " SITE.. EX Oat Out pt*tR oa 10 01 3««»f«« ecia TtJ«« sttBin « 10 TiJM fi-an OPlc Out Otic Out or 41 i vrvn OFbp Out Aai> or) tnh}/'<ti Vi sion. f oa M *» Jii M STK EX ilODS OA C003 04 work Ot tmst COOT OT s)ao3 OT 0«f3h 08 5N ffTK EX FORWARD ^ ^ic»h?i fe>&o.it| siejRte •Tl«a I I t €M STlf, EX Kif aiii'.-'i*' 0003 14 t la M l^m ^-.^'^ actnt, REVERSE FIGURE 4 BEST ORIGINAL QQ SE Ii. 0. 370 36-0 390 340 330 SW I I I ' 1 I I I I I I I t I I I I I I I I I I I , LINE1 y-(X UNE 3) A A'V*A***A'V*'*.*^'*A^A'*'^**A'V^W^A A^v -r-'t'-'-*'.'Ivlv'"V1*//' • •'••••-•--'»*'•'•••"••'.*'.• j.^.-'.-^s'\*v»v.'/-*.-*>.--**r'»v*'»V-'v AAAAA*,A-*.*»AAAAAA -^TSC'-V-V*''/*0-'-V-"'«''''.*-'^ ' *- '^^'I'.AlMir^'ir^C- 'l'-'.-^'U A A A AAAAAAAAAAA^Ao^AAA A 3I>»C^»;» •«:/>:/>:«>%-'.-*-.*'••--V -V' •' ^ » -^'**AAAA/iAAA A A% V-V-V. A A A A A A A AAAA^AAAAAAAAA l> 1% > |' \| i'n ,V .*,' ' ' ^ dr'-^ A A A A A AA A AAAAAAAAAAAAA Jt'% »'. ' *. * A AA AA A AA A A A AA A A AA A A A A A A A A A A A 2" JL A j." A" ^" ^" '•'V^^^-^AAAAAAA A TIT;-.*;* -l-. - **• •* * ^ ^ •* * * •* ^ * ^ * A A A A A A A Ji. A *. ^ * *• * * * * * * * * * A A A A A A A V. • < < <*: V41V V tVs: HORIZONTALSCALE 40ft - JLSO (DISTANCE IN FEET) 200 FIGURE 6 LINE 2 ^ *^- (XUNE3) D E 3 BEST ORIGINM 360 iii 390 tt. as 0. 340 Ul Q 330 (XUNE2) I »' I I I ''''''' ' LINES ^ ^PCUNEI) A A A A a- A AA AA A AA * A A A A VERTICAL SCALE 0 15ft HORi^WTAL SCALE 0 soft 320 h 1 I I i I I I I t 1 1 i I 1 t I I I I . 1 ^ I I . . 50 l-OO XSO (DISTANCE IN FEET) 'I' I' I' I ''''»«»«' 1 ••»' f t" 2SO 3GO FIGURE 8 N I I t I I ''''''''' I I ' '' UNE 4 370 2 -•360 390 340 " ' ' ' I • 1 I . . ." O 20 40 £0 80 (DISTANCE IN FEET) 10b 120 ft FIGURE 9 BEST ORIGIN, LINES 370 Ul u. 360 350 Ul Q 340 330 4592 ft/'s t r, A » * It t » A A » > . ^ VERTICAL SCALE HORtZONTAL SCALE J.'''««'' 'I I »>'»«»''' I''' •' I«111....... i. II ^ O so lOO X50 2oa (DISTANCE IN FEET) 3S0 FIGURE 10 SW 370 36a I Ul O 340 NE -'^ ' I i «''«''« I ' t I I I I r r r i i | i i i t i i i i i | i i i i i , , , , | j, LINE 6 ^saaasHHHai^ HORIZONTALSCALE 50ft 330 « i I I I » I I I t f I t I . . . , . , , t »0 AOO A50 (DISTANCE IN FEET) aoo xso Bt51 0R16INAI FIGURE 11 w 360 m u. Q. Ul Q I A 940 LINE 7 * e c o * *,* *r **• **• I* A* I* ** r* ** ^* *•* ** "•^ ** *•* ** "-^ "v "^fc "V %, '\ %, *^ * " ^ J.-** *2*2*2* *A \ "A^«*^ *^ \. \\ \ \ *• * * * * » *• * A * A A A. \ A *x.'\,'**. ^.^ '^^'•"x \ \ '\ •'•^ \ \ \ ^ * A A A'' A" A' VERTICAL SCALE 50ft xso (DISTANCE IN FEET) FIGURE 12 3«0 s I I r Ul Q 390 330 320 ' ' ' « ' t ' » I I T I » I I I I I I I I I I I I I I I LINE 8 c o N E - VERTICAL SCALE 0 15ft HORgQHTAL SCALE Bsasssssssa^ so ' ' t I I I I i t 1 I 1 » t I . . . . i . . . , JlOO iSO (DISTANCE IN FEET) acM3 2SO NAb IGURE 13 Appendix E Leighton Consulting, Inc. GENERAL EARTHWORK AND GRADING SPECIFICATIONS Page 1 of 6 LEIGHTON CONSULTING, INC. GENERAL EARTHWORK AND GRADING SPECIFICATIONS FOR ROUGH GRADING LO General Ll Intent: These General Earthwork and Grading Specifications are for the grading and earthwork shown on the approved grading plan(s) and/or indicated in the geotechnical report(s). These Specifications are a part of the recommendations contained in the geotechnical report(s). In case of conflict, the specific recommendations in the geotechnical report shall supersede these more general Specifications. Observations of the earthwork by the project Geotechnical Consultant during the course of grading may result in new or revised recommendations that could supersede these specifications or the recommendations in the geotechnical report(s). 1 -2 The Geotechnical Consultant of Record: Prior to commencement of work, the owner shall employ the Geotechnical Consultant of Record (Geotechnical Consultant). The Geotechnical Consultants shall be responsible for reviewing the approved geotechnical report(s) and accepting the adequacy of the preliminary geotechnical findings, conclusions, and recommendations prior to the commencement of the grading. Prior to commencement of grading, the Geotechnical Consultant shall review the "work plan" prepared by the Earthwork Contractor (Contractor) and schedule sufficient personnel to perform the appropriate level of observation, mapping, and compaction testing. During the grading and earthwork operations, the Geotechnical Consultant shall observe, map, and document the subsurface exposures to verify the geotechnical design assumptions. If the observed conditions are found to be significantly different than the interpreted assumptions during the design phase, the Geotechnical Consultant shall inform the owner, recommend appropriate changes in design to accommodate the observed conditions, and notify the review agency where required. Subsurface areas to be geotechnically observed, mapped, elevations recorded, and/or tested include natural ground after it has been cleared for receiving fill but before fill is placed, bottoms of all "remedial removal" areas, all key bottoms, and benches made on sloping ground to receive fill. The Geotechnical Consultant shall observe the moisture-conditioning and processing of the subgrade and fill materials and perform relative compaction testing of fill to determine the attained level of compaction. The Geotechnical Consultant shall provide the test results to the owner and the Contractor on a routine and frequent basis. 3030.1094 Leighton Consulting, Inc. GENERAL EARTHWORK AND GRADING SPECIFICATIONS Page 2 of 6 L3 The Earthwork Contractor: The Earthwork Contractor (Contractor) shall be qualified, experienced, and knowledgeable in earthwork logistics, preparation and processing of ground to receive fill, moisture-conditioning and processing of fill, and compacting fill. The Contractor shall review and accept the plans, geotechnical report(s), and these Specifications prior to commencement of grading. The Contractor shall be solely responsible for performing the grading in accordance with the plans and specifications. The Contractor shall prepare and submit to the owner and the Geotechnical Consultant a work plan that indicates the sequence of earthwork grading, the number of "spreads" of work and the estimated quantities of daily earthwork contemplated for the site prior to commencement of grading. The Contractor shall inform the owner and the Geotechnical Consultant of changes in work schedules and updates to the work plan at least 24 hours in advance of such changes so that appropriate observations and tests can be planned and accomplished. The Contractor shall not assume that the Geotechnical Consultant is aware of all grading operations. The Contractor shall have the sole responsibility to provide adequate equipment and methods to accomplish the earthwork in accordance with the applicable grading codes and agency ordinances, these Specifications, and the recommendations in the approved geotechnical report(s) and grading plan(s). If, in the opinion of the Geotechnical Consultant, unsatisfactory conditions, such as unsuitable soil, improper moisture condition, inadequate compaction, insufficient buttress key size, adverse weather, etc., are resulting in a quality of work less than required in these specifications, the Geotechnical Consultant shall reject the work and may recommend to the owner that construction be stopped until the conditions are rectified. 2.0 Preparation of Areas to be Filled 2.1 Clearing and Grubbing: Vegetation, such as brush, grass, roots, and other deleterious material shall be sufficiently removed and properly disposed of in a method acceptable to the owner, governing agencies, and the Geotechnical Consultant. The Geotechnical Consultant shall evaluate the extent of these removals depending on specific site conditions. Earth fill material shall not contain more than 1 percent of organic materials (by volume). No fill lift shall contain more than 5 percent of organic matter. Nesting of the organic materials shall not be allowed. If potentially hazardous materials are encountered, the Contractor shall stop work in the affected area, and a hazardous material specialist shall be informed immediately for proper evaluation and handling of these materials prior to continuing to work in that area. As presently defined by the State of California, most refined petroleum products (gasoline, diesel fiiel, motor oil, grease, coolant, etc.) have chemical constituents that are considered to be hazardous waste. As such, the indiscriminate dumping or spillage of these fluids onto the ground may constitute a misdemeanor, punishable by fines and/or imprisonment, and shall not be allowed. 3030.1094 Leighton Consulting, Inc. GENERAL EARTHWORK AND GRADING SPEQRCATIONS Page 3 of 6 2.2 Processing: Existing ground that has been declared satisfactory for support of fill by the Geotechnical Consultant shall be scarified to a minimum depth of 6 inches. Existing ground that is not satisfactory shall be overexcavated as specified in the following section. Scarification shall continue until soils are broken down and free of large clay lumps or clods and the working surface is reasonably uniform, flat, and free of uneven features that would inhibit uniform compaction. 2-3 Overexcavation: In addition to removals and overexcavations recommended in the approved geotechnical report(s) and the grading plan, soft, loose, dry, saturated, spongy, organic-rich, highly fractured or otherwise unsuitable ground shall be overexcavated to competent ground as evaluated by the Geotechnical Consultant during grading. 2.4 Benching: Where fills are to be placed on ground with slopes steeper than 5:1 (horizontal to vertical units), the ground shall be stepped or benched. Please see the Standard Details for a graphic illustration. The lowest bench or key shall be a minimum of 15 feet wide and at least 2 feet deep, into competent material as evaluated by the Geotechnical Consultant. Other benches shall be excavated a minimum height of 4 feet into competent material or as otherwise recommended by the Geotechnical Consultant. Fill placed on ground sloping flatter than 5:1 shall also be benched or otherwise overexcavated to provide a flat subgrade for the fin. 2-5 Evaluation/Acceptance of Fill Areas: All areas to receive fill, including removal and processed areas, key bottoms, and benches, shall be observed, mapped, elevations recorded, and/or tested prior to being accepted by the Geotechnical Consultant as suitable to receive fill. The Contractor shall obtain a written acceptance from the Geotechnical Consultant prior to fill placement. A licensed surveyor shall provide the survey control for determining elevations of processed areas, keys, and benches. 3.0 Fill Material 3.1 General: Material to be used as fill shall be essentially free of organic matter and other deleterious substances evaluated and accepted by the Geotechnical Consultant prior to placement. Soils of poor quality, such as those with unacceptable gradation, high expansion potential, or low strength shall be placed in areas acceptable to the Geotechnical Consultant or mixed with other soils to achieve satisfactory fill material. 3.2 Oversize: Oversize material defined as rock, or other irreducible material with a maximum dimension greater than 8 inches, shall not be buried or placed in fill unless location, materials, and placement methods are specifically accepted by the Geotechnical Consultant! Placement operations shall be such that nesting of oversized material does not occur and such that oversize material is completely surrounded by compacted or densified fill. Oversize material shall not be placed within 10 vertical feet of finish grade or within 2 feet of future utilities or underground construction. 3030.1094 Leighton Consulting, Inc. GENERAL EARTHWORK AND GRADING SPECIRCATIONS Page 4 of 6 3.3 Import: If importing of fill material is required for grading, proposed import material shall meet the requirements of Section 3.1. The potential import source shall be given to the Geotechnical Consultant at least 48 hours (2 working days) before importing begins so that its suitability can be determined and appropriate tests performed. 4.0 Fill Placement and Compaction 4.1 Fill Layers: Approved fill material shall be placed in areas prepared to receive fill (per Section 3.0) in near-horizontal layers not exceeding 8 inches in loose thickness. The Geotechnical Consultant may accept thicker layers if testing indicates the grading procedures can adequately compact the thicker layers. Each layer shall be spread evenly and mixed thoroughly to attain relative uniformity of material and moisture throughout. 4-2 Fill Moisture Conditioning: Fill soils shall be watered, dried back, blended, and/or mixed, as necessary to attain a relatively uniform moisture content at or slightly over optimum. Maximum density and optimum soil moisture content tests shall be performed in accordance with the American Society of Testing and Materials (ASTM Test Method Dl 557-07). 4-3 Compaction of Fill: After each layer has been moisture-conditioned, mixed, and evenly spread, it shall be uniformly compacted to not less than 90 percent of maximum dry density (ASTM Test Method D1557-07). Compacfion equipment shall be adequately sized and be either specifically designed for soil compaction or of proven reliability to efficiently achieve the specified level of compaction with uniformity. 4-4 Compaction of Fill Slopes: In addition to normal compaction procedures specified above, compaction of slopes shall be accomplished by backrolling of slopes with sheepsfoot rollers at increments of 3 to 4 feet in fill elevation, or by other methods producing satisfactory results acceptable to the Geotechnical Consultant. Upon completion of grading, relative compaction of the fill, out to the slope face, shall be at least 90 percent of maximum density per ASTM Test Method D1557-07. 4-5 Compacfion Testing: Field tests for moisture content and relative compaction of the fill soils shall be performed by the Geotechnical Consultant. Location and frequency of tests shall be at the Consultant's discretion based on field conditions encountered. Compaction test locations will not necessarily be selected on a random basis. Test locations shall be selected to verify adequacy of compaction levels in areas that are judged to be prone to inadequate compaction (such as close to slope faces and at the fill/bedrock benches). 4-6 Frequency of Compaction Testing: Tests shall be taken at intervals not exceeding 2 feet in vertical rise and/or 1,000 cubic yards of compacted fill soils embankment. In addifion, as a guideline, at least one test shall be taken on slope faces for each 5,000 square feet of slope face and/or each 10 feet of vertical height of slope. The Contractor shall assure that fill construction is such that the testing schedule can be accomplished by the Geotechnical Consultant. The Contractor shall stop or slow down the earthwork construction if these minimum standards are not met. 3030.1094 Leighton Consulting, Inc. GENERAL EARTHWORK AND GRADING SPECIFICATIONS Page 5 of 6 4-7 Compaction Test Locations: The Geotechnical Consultant shall document the approximate elevation and horizontal coordinates of each test location. The Contractor shall coordinate with the project surveyor to assure that sufficient grade stakes are established so that the Geotechnical Consultant can determine the test locations with sufficient accuracy. At a minimum, two grade stakes within a horizontal distance of 100 feet and vertically less than 5 feet apart from potential test locations shall be provided. 5.0 Subdrain Installation Subdrain systems shall be installed in accordance with the approved geotechnical report(s), the grading plan, and the Standard Details. The Geotechnical Consultant may recommend additional subdrains and/or changes in subdrain extent, location, grade, or material depending on conditions encountered during grading. All subdrains shall be surveyed by a land surveyor/civil engineer for line and grade after installation and prior to burial. Sufficient time should be allowed by the Contractor for these surveys. 6.0 Excavation Excavations, as well as over-excavation for remedial purposes, shall be evaluated by the Geotechnical Consultant during grading. Remedial removal depths shown on geotechnical plans are estimates only. The actual extent of removal shall be determined by the Geotechnical Consultant based on the field evaluation of exposed conditions during grading. Where fill-over-cut slopes are to be graded, the cut portion of the slope shall be made, evaluated, and accepted by the Geotechnical Consultant prior to placement of materials for construction of the fill portion of the slope, unless otherwise recommended by the Geotechnical Consultant. 3030.1094 Leighton Consulting, Inc. GENERAL EARTHWORK AND GRADING SPEQFICATIONS Page 6 of 6 7.0 Trench Backfills 7.1 The Contractor shall follow all OHSA and Cal/OSHA requirements for safety of trench excavations. 7.2 All bedding and backfill of utility trenches shall be done in accordance with the applicable provisions of Standard Specificafions of Public Works Construction. Bedding material shall have a Sand Equivalent greater than 30 (SE>30). The bedding shall be placed to 1 foot over the top of the conduit and densified by jetting. Backfill shall be placed and densified to a minimum of 90 percent of maximum from 1 foot above the top of the conduit to the surface. 7.3 The jetting of the bedding around the conduits shall be observed by the Geotechnical Consultant. 7.4 The Geotechnical Consultant shall test the trench backfill for relative compaction. At least one test should be made for every 300 feet of trench and 2 feet of fill. 7.5 Lift thickness of trench backfill shall not exceed those allowed in the Standard Specifications of Public Works Construction unless the Contractor can demonstrate to the Geotechnical Consultant that the fill lift can be compacted to the minimum relafive compaction by his altemafive equipment and method. 3030.1094 RLL SLOPE PROJECTED PLANE 1 TO 1 MAXIMUM FROM TOE OF SLOPE TO APPROVED GROUND EXISTING GROUND SURFACE BENCH HEIGHT (4' TYPICAL) REMOVE UNSUITABLE MATERIAL 2' MIN.—' KEY DEPTH LOWEST BENCH (KEY) FILL-OVER-CUT SLOPE EXISTING GROUND SURFACE T •-BENCH HEIGHT (4* TYPICAL) REMOVE UNSUITABLE MATERIAL CUT-OVER-FILL SLOPE -CUT FACE SHALL BE CONSTRUCTED PRIOR TO FILL PLACEMENT TO ASSURE ADEQUATE GEOLOGIC CONDITIONS EXISTING GROUND SURFACE PROJECTED PLANE 1 TO 1 MAXIMUM FROM TOE OF SLOPE TO APPROVED GROUND 2' MIN." KEY DEPTH UT FACE SHALL BE CONSTRUCTED PRIOR TO FILL PLACEMENT OVERBUILD AND TRIM BACK REMOVE UNSUITABLE MATERIAL BENCH HEIGHT (4* TYPICAL) FOR SUBDRAINS SEE STANDARD DETAIL C LOWEST BENCH (KEY) BENCHING SHALL BE DONE WHEN SLOPE'S ANGLE IS EQUAL TO OR GREATER THAN 5:1. MINIMUM BENCH HEIGHT SHALL BE 4 FEET AND MINIMUM FILL WIDTH SHALL BE 9 FEET KEYING AND BENCHING GENERAL EARTHWORK AND GRADING SPECIFICATIONS STANDARD DETAILS A FINISH GRADE SLOPE FACE ;C"6wArM"M"' * OVERSIZE ROCK IS LARGER THAN 8 INCHES IN LARGEST DIMENSION. * EXCAVATE A TRENCH IN THE COMPACTED FILL DEEP ENOUGH TO BURY ALL THE ROCK. * BACKFILL WITH GRANULAR SOIL JETTED OR FLOODED IN PLACE TO FILL ALL THE VOIDS. * DO NOT BURY ROCK WITHIN 10 FEET OF FINISH GRADE. * WINDROW OF BURIED ROCK SHALL BE PARALLEL TO THE FINISHED SLOPE. GRANULAR MATERIAL TO BE DENSIFIED IN PLACE BY FLOODING OR JETTING. DETAIL "•JETTED OR FLOODED GRANULAR MATERIAL TYPICAL PROFILE ALONG WINDROW OVERSIZE ROCK DISPOSAL GENERAL EARTHWORK AND GRADING SPECIFICATIONS STANDARD DETAILS B BENCHING- •REMOVE UNSUITABLE MATERIAL SUBDRAIN TRENCH SEE DETAIL BELOW CALTRANS CLASS 2 PERMEABLE-^^ yy OR #2 ROCK (9FT"3/FT) WRAPPED IN FILTER FABRIC // FILTER FABRIC (MIRAFI UON OR APPROVED EQUIVALENT)* 4" MIN. BEDDING COLLECTOR PIPE SHALL BE MINIMUM 6" DIAMETER SCHEDULE 40 PVC PERFORATED PIPE. SEE STANDARD DETAIL D FOR PIPE SPECIFICATIONS SUBDRAIN DETAIL DESIGN FINISH GRADE NONPERFORATED 6 0 MIN 6 0MIN. PIPE FILTER FABRIC (MIRAFI 140N OR APPROVED EQUIVALENT) CALTRANS CLASS 2 PERMEABLE OR #2 ROCK (9FT'^3/FT) WRAPPED IN FILTER FABRIC DETAIL OF CANYON SUBDRAIN OUTLET CANYON SUBDRAINS GENERAL EARTHWORK AND GRADING SPECIFICATIONS STANDARD DETAILS C 15* MIN. OUTLET PIPES / 4" 0 NONPERFORATED PIPE. /lOO' MAX. OC. HORIZONTALLY, 30' MAX OC. VERTICALLY BACK CUT 1:1 OR FLATTER SEE SUBDRAIN TRENCH DETAIL LOWEST SUBDRAIN SHOULD BE SITUATED AS LOW AS POSSIBLE TO ALLOW SUITABLE OUTLET -KEY DEPTH (2' MIN.) KEY WIDTH AS NOTED ON GRADING PLANS (15" MIN.) 12" MIN. OVERLAP- FROM THE TOP HOG RING TIED EVERY 6 FEET CALTRANS CLASS PERMEABLE OR #2 ROCK (3 FT''3/FT) WRAPPED IN FILTER FABRIC 4" 0 NON-PERFORATED OUTLET PIPE PROVIDE POSITIVE SEAL AT THE JOINT T-CONNECTION FOR COLLECTOR PIPE TO OUTLET PIPE 6 MIN. COVER 4" 0 PERFORATED PIPE FILTER FABRIC ENVELOPE (MIRAFI 140 OR APPROVED EQUIVALENT) 4" MIN. BEDDING SUBDRAIN TRENCH DETAIL SUBDRAIN INSTALLATION - subdrain collector pipe sholl be instolled with perforotion down or. unless otherwise designoted by the geotechnicol consultont. Outlet pipes sholl be non-perforoted pipe. The subdroin pipe sholl hove ot leost 8 perforotions uniformly spoced per foot. Perforotion sholl be 1/4" to 1/2" if drill holes ore used. All subdrain pipes shall hove o qrodient of ot leost 2% towords the outlet. SUBDRAIN PIPE - Subdroin pipe sholl be ASTM D2751. SDR 23.5 or ASTM 01527. Schedule 40 or ASTM D3034, SDR 23.5. Schedule 40 Polyvinyl Chloride Plostic (PVC) pipe. All outlet pipe sholl be placed in o trench no wide thon twice the subdroin pipe. Pipe sholl be in soil of SE >/=30 jetted or flooded in ploce except for the outside 5 feet which sholl be notive soil bockfill. BUTTRESS OR REPLACEMENT FILL SUBDRAINS GENERAL EARTHWORK AND GRADING SPECIFICATIONS STANDARD DETAILS D SOIL BACKFILL, COMPACTED TO 90 PERCENT RELATIVE COMPACTION BASED ON ASTM D1557 RETAINING WALL- WALL WATERPROOFING PER ARCHITECT'S SPECIFICATIONS FINISH GRADE WALL FOOTING FILTER FABRIC ENVELOPE '(MIRAFI UON OR APPROVED EQUIVALENT)** -3/4" TO 1-1/2" CLEAN GRAVEL -4" (MIN.) DIAMETER PERFORATED PVC PIPE (SCHEDULE 40 OR EQUIVALENT) WITH PERFORATIONS ORIENTED DOWN AS DEPICTED MINIMUM 1 PERCENT GRADIENT TO SUITABLE OUTLET -3" MIN. COMPETENT BEDROCK OR MATERIAL AS EVALUATED BY THE GEOTECHNICAL CONSULTANT NOTE- UPON REVIEW BY THE GEOTECHNICAL CONSULTANT. COMPOSITE DRAINAGE PRODUCTS SUCH AS MIRADRAIN OR J-DRAIN MAY BE USED AS AN ALTERNATIVE TO GRAVEL OR CLASS 2 PERMEABLE MATERIAL INSTALLATION SHOULD BE PERFORMED IN ACCORDANCE WITH MANUFACTURER'S SPECIFICATIONS. RETAINING WALL DRAINAGE DETAIL GENERAL EARTHWORK AND GRADING SPECIFICATIONS STANDARD DETAILS E