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HomeMy WebLinkAboutCT 02-28; La Costa Condominiums; Revised update Geotechnical Report; 2008-02-14VISED -*-* I ROPOSED A COSTA :ONDOMINIUMS 'ebtuary 14,2008 ,N. 23280.01 C acific Center Blvd. 22725 Old Canal Rd. Suite 112 Yorba Linda, CA 92887 San Diego, CA 92121 AmericanGeotechnical Inc. 5600 Spring Mtn. Rd. 712 Fifth Street, Suite 201 Suite B Las Vegas, NV 89146 Davis, CA95616 SOIL, FOUNDAHON & GEOLOGIC STUDIES American Geotechnicaljnc. SOIL, FOUNDATION AND GEOLOGIC STUDIES February 14, 2008 File No. 23280.01 Mr. Kwan So CALSO, LLC 2683 Costebelle Drive La Jolla, California 92037 Subject: REVISED UPDATE GEOTECHNICAL REPORT PROPOSED LA COSTA CONDOMINIUMS Lot 185, La Costa Avenue South - Unit 1 Carlsbad Tract No. 02-28 Carlsbad, California Dear Mr. So: American Geotechnical is pleased to present this revised update geotechnical report for the property referenced above, The purpose of our study was to review previous work performed at the site, assess current geologic/geotechnical conditions and to present recommendations for the proposed development. Results of the investigation indicate that proposed development is feasible, however, the site possesses many adverse geotechnical/geologic conditions that will impact site development and require special attention before, during and after construction, Of most immediate concern is the presence of a recent slope failure on and below lot 47 (2416 Sacada Circle) and recent movement of other landslides along the southern slope. Also of special concern are the presence of ancient landslides and potentially unstable slopes along the southern portion of the planned development. The proposed project will require extensive landslide remediation along the north facing ascending slope on the south side of the proposed development. Because of the extensive remedial grading proposed, a full time site-monitoring program is necessary during remedial grading for landslide treatment. An accompanying report entitled "Remedial Grading Procedures" has been prepared to address these conditions. This report and the recommendations contained herein should be incorporated into the project plans and specifications. Recommendations for grading, foundation design, and other improvements are presented in the following report. This geotechnical report should be reviewed in detail prior to proceeding further with the planned development. Should you have any questions regarding the information herein, please do not hesitate to contact this office. When additional plans become available, they should be forwarded to this office for review and comment. 22725 Old Canal Road, Yorba Linda, CA 92887 • (714) 685-3900 • FAX (714) 685-3909 5600 Spring Mountain Road, Suite 201, Las Vegas, NV 89146 • (702) 562-5046 • FAX (702) 562-2457 5764 Pacific Center Blvd., Suite 112, San Diego, CA 92121 • (858) 450-4040 • FAX (858) 457-0814 712 Fifth Street, Suite #B, Davis, CA 95616 • (530) 758-2088 • FAX (530) 758-3288 File No. 23280.01 February 14, 2008 Page 2 llAmerican Geotechnicaljnc. We appreciate the opportunity to be of service. If you should have any questions, please do not hesitate to contact us. Sincerely, AMERICAN GEOTECHNICAL Edred T. Marsh Principal Engineer G.E. 2387 ^ £. 9- Kevin Rogers Senior Geologist C.E.G2435 ETM/CC/KR: ks Distribution: Mr. Kwan So - (5) Craig Chase Chief Engineering Geologist C.E.G. 2225 Via Mail ffl American Geotechnicaljnc SOIL, FOUNDATION AND GEOLOGIC STUDIES TABLE OF CONTENTS 1.0 INTRODUCTION 3 1.1 Purpose , 3 1.2 Proposed Development , 3 1.3 Scope of Services , 3 2.0 SITE DESCRIPTION 4 3.0 PREVIOUS SITE INVESTIGATIONS 5 4.0 GEOLOGY 5 4.1 Geologic Setting 5 4.2 Site Specific Geology 6 4.3 Geologic Hazards , 8 4.4 Seismicity and Seismic Risk 10 4.4.1 Liquefaction 10 4.5 Groundwater 11 5.0 CONCLUSIONS 12 6.0 RECOMMENDATIONS , 13 6.1 General 13 6.2 Earthwork 13 6.2.1 Site Preparation 13 6.2.2 Cuts and Excavations 13 6.2.3 Removal of Unsuitable Soils 14 6.2.4 Fills 14 6.2.5 Material Volume Changes 16 6.2.6 Cut/Fill Transitions and Lot Capping 16 6.3 Slopes and Slope Stability .17 6.4 Foundation and Slab Design Parameters ,..,, .....20 6.5 Standard Foundation Recommendations 22 6.5.1 Slab and Footings (Non-Low Expansivity) 22 6.5.2 Appurtenant Structures , 23 6.5.3 Reinforcement Placement 24 6.6 Retaining Wall Design Criteria 24 6.7 Preliminary Pavement Design 25 6.8 Site Drainage 26 6.9 Utilities 27 6.10 Corrosivity 27 6.11 Geotechnicai Services During Construction 27 6.12 Plan Review , 27 22725 Old Canal Road, Yorba Linda, CA 92887 • (714) 685-3900 • FAX (714) 685-3909 5600 Spring Mountain Road, Suite 201, Las Vegas, NV 89146 • (702) 562-5046 • FAX (702) 562-2457 5764 Pacific Center Blvd., Suite 112, San Diego, CA 92121 • (858) 450-4040 • FAX (858) 457-0814 712 Fifth Street, Suite #B, Davis, CA 95616 • (530) 758-2088 • FAX (530) 758-3288 HAmerican Geotechnicaljnc. TABLE OF CONTENTS (CONTINUED) 7.0 OTHER CONSIDERATIONS 28 7.1 Project Safety 28 8.0 REMARKS 28 FIGURE 1 - SITE LOCATION MAP FIGURE 2 - CUT-OFF TRENCH DRAIN DETAIL FIGURE 3 - SUB-SLAB RECOMMENDATIONS APPENDIX A - REFERENCES APPENDIX B - SUBSURFACE LOGS APPENDIX C - LABORATORY TEST PROCEDURES/RESULTS APPENDIX D - SLOPE STABILITY APPENDIX E - SEISMIC EVALUATION RESULTS APPENDIX F - STANDARD GUIDELINES FOR GRADING PLATE 1 - GEOTECHNICAL MAP PLATES 2 & 3 - GEOLOGIC CROSS SECTIONS File NO 2328001 H American Geotechnical, Inc. February 14, 2008 Page3 1.0 INTRODUCTION 1.1 Purpose The following text presents the results of our Geotechnical update for the site of the proposed La Costa Condominium project located in the City of Carlsbad, California (see Figure 1, Site Location Map), The purpose of our study was to review previous work performed at the site, assess current geologic/geotechnical conditions and to present recommendations for the proposed development. 1.2 Proposed Development Based upon our recent conversations and review of the latest grading plans prepared by O'Day Consultants, Inc., (see references) it is our understanding that the proposed development will consist of site grading and the construction of approximately 58 condominium units in 12 buildings, a recreation area, typical associated site improvements such as interior roadways and parking areas, retaining walls, utilities and other appurtenant structures. It is our understanding that some of the buildings will be split-level and that the current plan for all building foundations is the use of continuous footings with slab-on-grade floor systems. As grading and/or architectural/foundation plans are completed, they should be forwarded to this office for review. 1.3 Scope of Services The scope of work performed during our investigation included the following: • Review of available literature and maps pertaining to geotechnical conditions at the site and surrounding area. References are presented in Appendix A. • Review of previous subsurface investigations at the site conducted by American Geotechnical and other firms. The previous investigations are referenced in Appendix A. » Engineering and geologic analysis of all available data to develop grading, foundation and other soil related design parameters for development. • Preparation of this updated report including conclusions and recommendations for site geotechnical/geologic considerations during site development. Approximate location of site SK*\ T13S:-.• PACIFIC OCEAN American Geotechnical, Inc. La Costa Condos Site Location Map F.N. 23820.01 Figure 1 File NO 2328001 HJAiTierican Geotechnical, Inc. February 14, 2008 Page 4 2.0 SITE DESCRIPTION Review of the project grading plans indicates that the property encompasses approximately 8 acres of nearly flat to steeply sloping terrain. The site consists of a gently sloping previously graded main pad dominating the middle of the site surrounded by relatively high, moderately steep to steep ascending slopes to the south and east, a smaller descending slope to the north and an existing condominium development to the west. Topographically, the site ranges from a high of about 210 feet above mean sea level (msl) near the southeast portion of the site to about 80 feet above msl along the northwestern portion of the site, The site was previously graded which has resulted in fill soils covering most of the site. Grading apparently occurred in about 1970 under the observation and testing of Benton Engineering, Inc. Grading has also occurred along the southern portion of the site and off-site to the south. On-site natural and manufactured slopes generally have inclinations of about 2:1 (horizontal to vertical) and off-site fill slopes that cap the top of the ridgeline are as steep asl .5:1 (horizontal to vertical) in many locations. The existing slopes along the south and southeastern portions of the site have moderate to dense vegetation and trees and range from about 75 to 100 feet in height, The small graded slope that descends to La Costa Avenue to the north ranges from about 10 to 25 feet in height. The slopes to the south have performed poorly over time. A slope failure occurred during the winter of 2004/2005 that will require remediation (AG 2007 - Appendix A) and surficial slumping and erosion has occurred in many areas along this north-facing slope. Lower level movement along other landslide complexes was also identified. Drainage from properties to the south is directed over the slope in many areas and drainage devices and swales have not been maintained over time. It is recommended that these conditions be addressed (where possible) during construction. File NO 2328001 HAmerican Geotechnical, Inc. February 14,2008 Page5 3.0 PREVIOUS SITE INVESTIGATIONS Our review of the referenced documents indicates that Benton Engineering, Inc. performed a geotechnical investigation consisting of five large diameter borings and associated testing along the hillside on the south side of the project site (Benton, 1979 - Appendix A). The locations of these borings are shown on the Geotechnical Map (Plate 1) contained at the end of the report. Copies of the subsurface logs are included in Appendix B. Leighton and Associates conducted a geotechnical investigation in 1998, which was summarized in the referenced report (Leighton, 1999 - Appendix A) and later update report (Leighton, 2002). The investigation consisted of 7 small diameter borings and 11 large diameter borings and associated testing. The locations of these borings are shown on the Geotechnical Map (Plate 1) contained at the end of the report. Copies of the subsurface logs are included in Appendix B, American Geotechnical performed an investigation at the site associated with the slope failure that occurred on the north-facing slope on and below lot 47 - 2416 Sacada Circle during the winter of 2004/2005. Our investigation consisted of two large diameter borings (AGLB-1, AGLB-2) and three test pits (AGTP-1, AGTP-2, AGTP-3) and associated testing performed in 2006. AGLB-1 was drilled with a 30-inch diameter truck mounted bucket auger and AGLB-2 was drilled with a 24- inch limited access bucket rig. Both borings were sampled using a California modified split spoon sampler. The investigation was performed in order to develop a repair plan for the affected area. The results of that investigation and the associated repair plan are contained in a report that is referenced in Appendix A (American Geotechnical, 2007). The subsurface logs from that investigation are included in Appendix B. Recent laboratory testing was performed and the results are included in Appendix C. 4.0 GEOLOGY 4.1 Geologic Setting The subject property is located within the narrow coastal plain of the Peninsular Ranges geomorphic province of Southern California. Flat-topped mesas dissected by numerous canyons and alluvial valleys dominate the Southern California coastal plain geomorphology. The coastal mesas were formed by wave-cut erosion, and in geomorphic terms they are known as abrasion platforms or marine terraces. The marine terraces were uplifted relative to present day sea level File NO 2328001 HAmerican Geotechnical, Inc. February 14, 2008 Page 6 by tectonic forces, and have since been eroded by numerous temporal streams and rivers that have created the many canyons and alluvial valleys in the area, such as the one in which the site is located. The coastal plain of southern California is predominately underlain with sedimentary rocks derived from detritus eroded from the Peninsular Ranges Batholith located to the east. Published geologic maps of the area indicate the site is underlain by Eocene-aged sedimentary bedrock formally named the Santiago Formation. Locally, the bedrock has been weathered and eroded to form surficial deposits of topsoil/slopewash, and colluvium. In addition, several landslides have been identified on the existing slopes of the property. No faults have been mapped on the site and no evidence of faulting was found during our investigation. 4.2 Site Specific Geology Geotechnical investigations performed by our firm and others have found that the site is underlain by the Eocene-aged Santiago Formation, topsoil/slopewash, colluvium, artificial fill, and several landslide deposits. Generalized descriptions of the geologic units encountered during our geotechnical investigation are provided in the following sections and Plate 1 depicts the distribution of geologic units encountered. Cross sections have been included on Plates 2 & 3, which delineate the subsurface conditions identified from borings performed at the site. Artificial Fill (Qaf) Subsurface investigation performed by American Geotechnical, Leighton and Associates, and Benton Engineering, found existing fill material underlying much of the site. The earlier phases of grading appear to have consisted of typical cut-and -fill operations to smooth out the ridges and slopes and natural drainages of the original topography. Engineered fill material was apparently placed during construction of the existing sheet pad under the observation and testing of Benton Engineering, Inc., which was reportedly documented in a report issued by Benton Engineering in 1970 (according to Leighton and Associates, 2002). This report was not available for review. Fill soils up to about 32 feet in depth were encountered during previous investigations performed at the site, According to our review of the Leighton boring logs and test results, the fill soils in general File NO 2328001 HAiTierican Geotechnical, Inc. February 14, 2008 Page? consist of moderately well-compacted silty to clayey sands, clayey silts and silty clays. The results of laboratory testing performed by Leighton and Associates on samples obtained from fill areas indicate a low potential for collapse for the granular materials and moderate to very high expansion potential for the clayey materials, Topsoil/Slopewash Topsoil was encountered in sections of the slopes not previously graded along the southern portion of the site. The topsoil observed generally consisted of sandy to silty clays and clayey sands derived from the underlying weathered bedrock. The topsoil was generally porous and contained roots and organic fragments. The topsoil thickness varies but is estimated to be generally about 2- 5 feet in thickness, Quaternary Colluvium (Qcol) Quaternary age colluvium was encountered in Boring B-2 (Leighton, 1999) underlying compacted fills within the limits of a buried drainage. The colluvium was generally damp to moist, dense to very dense, silty and clayey sands. Laboratory testing performed during the investigation indicated a low collapse potential. Quaternary Landslide Deposits (Qls) Two recent slope failures and two older landslide complexes were identified on the north-facing slopes located along the southern portion of the site, One of the landslide complexes extends off- site onto adjacent properties along the ridgeline to the south (Plate 1). Surficial slumping and erosion of weathered native material and previously placed stability fill has also occurred in many areas along these slopes. The Quaternary age landslide deposits generally consist of highly disturbed blocks of Santiago Formation siltstone, sandstone, and claystone, mixed with topsoil and slope fill material. The landslides occurred along shear surfaces developed within the claystone beds and laminations of the Santiago Formation. The two landslide complexes located at the southwest and southeast corners of the site appear to be old features that have been reactivated. The more recent slope failures occurred during the winter of 2004/2005. Remediation Plans for one of the recent slope failures, located on and below File NO 2328001 HAmerican Geotechnical, Inc. February 14, 2008 Pages 2416 Sacada Circle, were developed by our firm and recently submitted to the City of Carlsbad (AG, 2007 - Appendix A). The other slope failure and reactivated older landslide deposits are not considered stable. They will require remediation during site development as described in the grading procedures and recommendations sections of this report. Tertiary Santiago Formation (Tsa) The Tertiary age Santiago Formation encountered at the site consists of orange-tan to brown, white-to-gray, and light green sandstone and siltstone variably laminated with clay seams, and interbedded with olive green to dark gray massive claystone at depth. The bedrock is typically lighter colored, variably oxidized and weathered near the surface becoming less oxidized and darker with depth. The claystone beds in particular are highly fractured throughout the depths explored and therefore they can be expected to transmit groundwater through the secondary porosity of the fractures. Some very hard, laterally continuous, cemented siltstone and sandstone beds were encountered at different depths and locations at the site. Perched groundwater was observed seeping from fractures contained within the cemented beds in some of the exploratory borings. The claystone and any fill material derived from the claystone can be expected to be highly to very highly expansive. Planned slopes constructed within fractured claystones will require stabilization fills and buttresses to be placed during grading. In previous reports the Santiago Formation was identified and mapped as the Delmar Formation and the Torrey Sandstone. Published geologic mapping performed by Tan and Kennedy (1996) re- named this rock unit as the Santiago Formation. Therefore descriptions of the Delmar Formation and the Torrey Sandstone contained in previous reports should be considered synonymous with the Santiago Formation. 4.3 Geologic Hazards Several geologic hazards have been known to exist along the Southern California coastline. Those hazards generally consist of landsliding, the possibility of tsunamis immediately along the coastline and earthquakes and its related effects. Tsunamis are not considered to be a factor in the proposed development because of the location of the site relative to the shoreline. File NO 2328001 H American Geotechnical, Inc. February 14, 2008 Page 9 Of most immediate concern is the presence of a recent slope failure on and below lot 47 (2416 Sacada Circle) and recent movement of other landslides along the southern slope. Also of special concern are the presence of ancient landslides and potentially unstable slopes along the southern portion of the planned development. The proposed project will require extensive landslide remediation along the north facing ascending slope on the south side of the proposed development. Because of the extensive remedial grading proposed, a full time site-monitoring program is necessary during remedial grading for landslide treatment. Recommendations for stabilization of landslides and potential slope instability is included in Section 6.3, Another geologic hazard that could affect the site would be ground motion/ shaking in the event of an earthquake. Earthquake magnitude is related to ground motion. Therefore, with higher magnitude earthquakes larger areas will be subjected to longer durations of intense shaking. However, a moderate earthquake (less than magnitude 7,0) can produce locally strong ground motions and intense shaking similar to that of major earthquakes (magnitudes of 7.0 and above). This was clearly illustrated during the 1994 Northridge earthquake that had a magnitude of 6.7 but locally endured strong ground motions in some areas causing severe damage. Several factors will affect the intensity of shaking during an earthquake. These include, the magnitude of the earthquake, its style of faulting, local geologic conditions, proximity to the fault rupture, and the rupture geometry along the fault. As documented from the 1994 Northridge earthquake and other earthquake events, the near-source effects and local geologic conditions on shaking intensity need to be incorporated into seismic design and construction. The nearest known active fault to the site is the Rose Canyon Fault, which lies approximately 6.2 miles to the west of the project. The maximum magnitude earthquake estimated for the Rose Canyon fault is a (M) 6,9. The following table illustrates the characteristics of ground shaking estimated for the site from various nearby faults using an attenuation relationship provided by Bozorgnia, Campbell, Niazi generated by EQFAULT 3.0 (Blake, 2000): File Mo. 23280.01 February 14, 2008 Page 10 ^American Geotechnical, Inc. TABLE 1-SELECTED FAULTS FAULT NAME Rose Canyon Newport-lngiewood (offshore) Elsinore-Julian Coronado Bank APPROXIMATE DISTANCE (MILES) 6.2 11.2 24,5 21.1 MOMENT MAGNITUDE (M) 6,9 6,9 7,1 7.4 PEAK SITE ACCELERATION (6) 0.35 0,22 0,11 0.16 PEAK SITE ACCELERATION + 1 STANDARD DEVIATION 0.58 0,37 0,18 0.26 *Results of the deterministic seismic evaluation are included in Appendix E. 4.4 Seismicity and Seismic Risk Our historical search indicates that approximately 109 events have occurred within a 50-mile radius of the site with magnitudes (M) between 4.0 and 9,0, within the last 100 years. The largest event recorded within that time frame was a (M) 6,8 earthquake, approximately 48 miles from the site, which produced a site acceleration of about 0,04g at the site, Even with proper design in accordance with applicable codes, the possibility of damage occurring to structures cannot be ruled out in the event of a moderate to large earthquake near the site. This is the case for essentially all homes in Southern California therefore the risk for this site is no greater than other surrounding communities, The structure should be designed in accordance with the latest UBC criteria for seismic design, The site area should be categorized as a Seismic Zone 4. 4.4,1 Liquefaction Liquefaction is a process that occurs generally in cohesionless soils due to strong vibratory motion during earthquakes. Liquefaction generally occurs at depths shallower than 100 feet and primarily in the upper 50 feet of the soil profile, Historical data indicates that loose granular soils and non- plastic sands and silts that are saturated due to shallow groundwater, are most susceptible to liquefaction during earthquake shaking. File NO 2328001 llAmerican Geotechnical, Inc. February 14, 2008 Page 11 If the soil is saturated and poorly consolidated and there is no possibility for drainage, so that constant volume conditions are maintained, shaking generates excess pore water pressure (Tokimatsu & Seed, 1984), Settlement then occurs as the excess pore pressure dissipates. In dry sands, the settlement occurs during the earthquake shaking under conditions of constant effective vertical stress. In order for liquefaction to occur, three general geotechnical characteristics are usually present: 1) Ground water (saturated conditions) must be present within the potentially liquefiable zone. 2) The soil in this zone must be granular and the grain size distribution must fall within a relatively specific range, 3) The soil must be of fairly low relative density. Due to the lack of groundwater in the planned building areas, the fine-grained and relatively firm nature of on-site soils, the potential for liquefaction to affect the planned development is considered low. 4.5 Groundwater Seepage was encountered in some of the exploratory borings, especially along the north-facing slope along the south side of the project. Groundwater seepage is generally occurring along claystone/siltstone structures where more permeable topsail and landslide debris overly these relatively impermeable layers. Perched groundwater conditions also variably occur within cemented/concreted zones encountered in some of the exploratory borings. After the recent slope failure on and below Lot 47 (2416 Sacada Circle) during the winter of 2004/2005, significant seepage was noted along the slope face and within the slide debris. Active surface seepage also occurs in various locations along the backcut of the access road cut along the south slope by Leighton and Associates during their geotechnical investigation, It is anticipated that both rainfall and irrigation from off-site properties located along the ridgeline to File NO 2328001 H American Geotechnical, Inc. February 14, 2008 Page 12 the south has and will continue to have an impact on site development and the overall performance of the project. To help mitigate this condition, it is recommended that stability fills with both subsurface and surface drainage systems be provided during site development along the southern slope areas. In addition, it is recommended that off-site drainage that is currently being directed over the southern slope be collected and directed to a suitable disposal area. Off-site drainage measures should ideally be incorporated into the planned surface drainage system being developed by the project civil engineer. Conceptually, the drainage system would consist of solid walled collector PVC pipes (or similar) directed to a planned concrete swale on the slope face or to the surface drainage or storm drain system on-site. The project civil engineer should develop the necessary details for this system. Shallow groundwater and seepage was not noted in exploratory borings located on the main building pad. However, it should be noted that surface or shallow perched groundwater conditions can and may develop in areas where no such condition existed prior to development. This can occur due to changes made to the natural drainage patterns during development, increased irrigation, heavy rainfall and/or other reasons. Because the introduction of water is usually the triggering mechanism for most common types of soil problems, it is typically useful to provide adequate surface drainage and drainage for proposed improvements such as retaining walls, foundation and slab areas and other improvements that could be adversely affected by water. General recommendations for drainage are provided in Section 6.8. 5.0 CONCLUSIONS Based upon the results of our geotechnical evaluation, it is our opinion that the proposed development is feasible, however, the site possesses many adverse geotechnical/geologic conditions that will impact site development and will require special attention before, during and after construction. The following conclusions and recommendations should be incorporated into the project plans and specifications for development of the site. File NO 2328001 IIAiTierican Geotechnical, Inc. February 14, 2008 Page 13 6.0 RECOMMENDATIONS 6.1 General Conclusions and recommendations contained in this report are based upon the information provided, information gathered, laboratory testing, engineering and geologic evaluations, experience, and professional judgment. Recommendations contained herein are consistent with industry practices. Other alternatives exist and can be discussed on request. Regardless of the approach taken, some risk will remain, as is always the case, 6.2 Earthwork Except as noted in the text of this report, all demolition, site preparation, and grading operations should be conducted as outlined in the Standard Guidelines for Grading projects, included as Appendix F, and should also be in conformance with the latest edition of applicable building codes and the City of Carlsbad grading requirements. 6.2.1 Site Preparation Grading is planned to some extent throughout the project to create level and split-level building pads for the planned structures and to create roads and other improvements for the planned development. Prior to grading, the site should be cleared of all surface and subsurface obstructions including things such as existing structures, fill, debris, buried utilities, and should be stripped of vegetation within the proposed pad areas. Vegetation and debris should be disposed of off site. Any holes or excavations made which extend below finished grade should be filled with compacted soil. 6.2.2 Cuts and Excavations Based on our visual observations and subsurface exploration at the site, the material present on- site can be excavated with conventional earth moving equipment. Excavating within the formational soils will generally vary in difficulty depending on the depth of the excavation and the degree of weathering. Cut pads and slope excavations will likely encounter moderately hard, but rippable rock. It is recommended that the earthwork contractor(s) visit the site and review this report in detail prior to submitting bids. File NO. 23280.01 HAmerican Geotechnical, Inc. February 14, 2008 Page 14 All permanent cut slopes planned for the development shall not be steeper than 2:1 (horizontal: vertical) unless approved by the geotechnical consultant. If excavations for cut slopes expose adverse bedding, unstable, loose, significantly fractured or otherwise unsuitable material, over- excavation and replacement of the unsuitable materials with a compacted stabilization fill should be accomplished as recommended by the geotechnical consultant. A member of our firm should be notified and be present to review all cut slopes and excavations prior to placing fill and/or foundation steel or concrete. Currently the two planned cut and cut/fill slopes within the project boundaries will receive stabilization fills as indicated on Plate 1. 6.2.3 Removal of Unsuitable Soils & Proposed Limits of Grading All areas planned to receive fills and/or improvements will require removal and re-compaction of loose, natural soil and/or unsuitable materials. Removal of loose near surface soil is expected to be on the order of five (5) feet for a majority of the site. Locally, deeper removals and re- compaction will likely be required. The geotechnical map and cross sections identify the proposed possible limits of grading, The actual depth and extent of required removals should be determined during grading operations by the on-site geotechnical consultant, The slope of on the eastern boundary of the site may require surficial remedial grading to remove any unsuitable or unstable surficial colluvium deposits. All removals should be inspected prior to placing fill. Removals associated with landslide complexes and slope stability issues are addressed in Section 6.3 and depicted on Plates 1-3 and Appendix D. 6.2.4 Fills Subsurface investigations indicate the presence of expansive soil throughout a majority of the site planned for building construction. It is recommended that expansive soils not be placed within five (5) feet of finish grade in the building pad areas or beneath appurtenant structures and should be kept a minimum of five (5) feet away from proposed structures, unless special design considerations are implemented. As an alternative, expansive soil can be blended with granular non-expansive soil and re-compacted to provide a structural fill that is non-expansive or of low expansivity. If this cannot be accomplished it will be necessary to revise the slab/foundation recommendations given in this report to reflect expansive soil conditions, With this exception, the File NO 2328001 H American Geotechnical, Inc. February 14, 2008 Page 15 on-site soils are considered suitable for use as compacted fill provided they are free of organic material and debris. A minimum of five (5) feet of structural fill should be provided for support of the residential structures. The limits of this work should extend a minimum of five (5) feet beyond the areal extent of the proposed foundations. It is also recommended that other improvements be supported on structural fill or competent natural material. The depth of structural fill will depend on the type of improvement being constructed, but should be considered to be the same as the building pads unless specific recommendations are requested. If imported soil is used for structural fill to achieve desired site grades, it must first be submitted to the geotechnical consultant for approval and additional testing, if necessary. In addition, the soil should generally conform to the following criteria: • Should be non-expansive or of low expansivity. • Should be free of oversized material (material greater than 8 inches). • Should be free of organic material and debris. • Should have less than 0.1 percent sulfate content. All fill to be placed should be moisture conditioned and compacted to a minimum of ninety (90) percent of the maximum dry density per ASTM D-l 557, Fill should be placed in thin, uniform lifts (6-8 inches loose thickness). Fills placed on natural slopes or cut slopes should be keyed and benched into firm, competent material and inspected prior to the placement of fill. Any permanently graded site slopes should be constructed at inclinations no steeper than 2:1 (horizontal to vertical), The geotechnical consultant should be on-site to test all fills/removals during grading operations. File NO 2328001 llAmerican Geotechnical, Inc. February 14, 2008 Page 16 6.2.5 Material Volume Changes It is anticipated that the grading process will create a volume change that will vary with material type and conditions created. It is expected that the excavation and re-compaction in soil areas will create a net loss or shrinkage, The following criteria can be used as estimates for earthwork calculations: Artificial fill 5% shrinkage Loose natural soil , 10%-15%shrinkage Moderately dense natural soil 5% -10% shrinkage Landslide debris 5%-10% shrinkage Weathered bedrock or bedrock 0% to 5% bulking Plate 1 depicts general geologic and soil information as well as the excavation locations. Appendix B includes detailed logs of subsurface excavations, 6.2.6 Cut/Fill Transitions and Lot Capping Structures planned for the development should not straddle cut/fill transitions, It is recommended that the cut portion of the pad be over-excavated to a minimum depth of five (5) feet below finish grade and at least 3 feet below the base of the footings. A properly compacted structural fill blanket should then be placed in the resulting excavation. The limits of this work should extend a minimum of five (5) feet beyond the aerial extent of proposed improvements (i.e., beyond the limits of the building and appurtenances). The geotechnical consultant should observe the bottom of the excavated areas at the time of grading to assess the quality of exposed material, and to evaluate if additional removals or recommendations are required. File NO 2328001 HAiTierican Geotechnical, Inc. February 14, 2008 Page 17 6.3 Slopes and Slope Stability Any permanently graded site slopes should be constructed at inclinations no steeper than 2:1 (horizontal to vertical) unless approved by the geotechnical consultant. Review of the most recent grading plans (O'Day, 2005), indicates both cut/fill and fill slopes on the order of 20-30 feet in height are planned for the subject site. These slopes are planned to be constructed at inclinations of 2:1 (horizontal: vertical), consistent with minimum code requirements. Natural slopes along the southern portion of the project will require remediation during grading to remove landslide complexes, landslide debris and to provide stability fills and drainage facilities. Off-site 1.5:1 fill slopes cap the southern ridgeline above the proposed project. These slopes are subject to surficial stability issues. As for the new, 2:1 slopes, history as demonstrated throughout southern California that 2:1 slopes are far less likely to experience surficial instability particularly if the compacted fill slopes are constructed by overfilling and cutting back to the compacted inner core. When occasional instabilities do occur they are typically localized and have been triggered by severe moisturization either by a pipe or irrigation problem or an unusually prolonged and heavy rainfall. As such, for typical 2:1 manufactured slopes we recommend deep rooted drought tolerant landscape, The various planned slopes and existing slopes were analyzed utilizing the slope stability program SLOPE/W (Geo-Slope, 2001). The results of the slope stability analysis are presented in Appendix D and a summary is presented in the following sections. Fill Slopes Our analysis indicates that fill slopes planned for the pad area constructed at a 2:1 (horizontal to vertical) or flatter inclination up to 30 feet in height will have an adequate factor of safety (F.S. > 1.50) against deep-seated slope failure. The proposed slopes should be constructed in accordance with the recommendations of this report and the City of Carlsbad grading requirements. RieNO 2328001 HAmerican Geotechnical, Inc. February 14,2008 Page 18 Surficial stability (i.e. shallow failures and erosional features) should be addressed during design and construction of proposed slopes. It is recommended that slopes be planted immediately following grading to help mitigate the potential for surficial instability and erosion. Erosion resistant plants should be used in slopes, preferably deep-rooted varieties adapted to semi- arid climates. Heavy bodied, shallow-rooted varieties such as ice plant should be avoided. In addition, drainage should not be allowed to flow over slopes. Surface water should be directed away from the top of slopes. Cut Slopes Any planned cut slopes will require full time monitoring by a geologist. If adverse conditions are identified such as weak, fractured claystone or otherwise undesirable conditions are exposed, additional removals and/or construction of stabilization fills will be required. Our experience with similar projects built on similar materials indicates that "perched" groundwater conditions and/or seepage may develop within slope profiles (especially cut and cut/fill transition slopes). It is recommended that adequate drainage devices be installed along the slope face and along the base of planned slopes, Consideration should be given to providing cut-off trench drains at the toe of planned cut and cut/fill slopes. A typical cut-off trench drain detail is depicted on Figure 2. Southern Slope - Landslide and Slope Stabilization Of most immediate concern is the presence of a recent slope failure on and below lot 47 (2416 Sacada Circle) and recent movement of other landslides along the southern slope. American Geotechnical performed an investigation at the site associated with the slope failure that occurred on the north-facing slope on and below lot 47 (2416 Sacada Circle) during the winter of 2004/2005. Our investigation consisted of two large diameter borings and three test pits and associated testing. The investigation was performed in order to develop a repair plan for the affected area. The results of that investigation and the associated repair plan are contained in a report that is referenced in Appendix A (American Geotechnical, 2007), 6 in. atrium drain grates @ max. 15 ft. spacing, or similar as field conditions dictate; direct surface drainage @ 2% min. to drain grates. - Compacted native granular soil minimum 8 in. soil cover. 4 ft. minimum a 4 in. solid schedule 40 pvc pipe or similar, min. 1% gradient Non-woven filter fabric such as Mirafi 140N or similar, 12 in. overlap @ splices 3/4 in. open graded rock thoroughly tamped in thin lifts. 4 in. schedule 40 pvc perforated pipe. Place perforations down. Slope at 1.5% min. Change to solid 4 in. pipe at the sidewalk of each respective lot before connecting to storm drain. Sketch not to scale American Geotechnical, Inc. La Costa Condos Cut-Off Trench Drain F.N. 23820.01 Figure 2 File NO 2328001 IIAiTierican Geotechnical, Inc. February 14, 2008 Page 19 Also of special concern are the presence of ancient landslides and potentially unstable slopes along the southern portion of the planned development. Because of these conditions, the proposed project will require extensive landslide remediation within this area. During the remedial grading, a full time site-monitoring program is recommended above the areas planned for remediation. An accompanying report entitled "Remedial Grading Procedures" has been prepared to address these conditions. The approximate locations of the planned stability buttresses and landslide removal areas are shown on the Geologic Map (Plate 1), the Geologic Cross Sections (Plates 2 & 3) and the slope stability analysis sections included in Appendix D. The stability fill keys should be constructed with a minimum width of Vz the slope height or a 15-foot minimum width, a depth of at least 5 feet below the toe-of-slope grade, with the key bottom sloped at a minimum of two percent into the slope, Off-Site Fill Slopes Off-site, 1.5:1 (horizontal: vertical) fill slopes cap the ridgeline above the southern property boundary. Slope stability analysis performed on these slopes indicates that the slopes are subject to surficial failures if seepage develops parallel to the slope face. This condition can occur during sustained periods of moderate to heavy rainfall. If one of these slopes were to experience a failure, there could be some impact on the proposed condominium development below. Ideally, these slopes could be re-built with geo-grid reinforcement to increase the factor-of-safety against surficial failures. If this cannot be accomplished, there still remains a higher risk for future slope problems. Other measures, such as the construction of additional retaining structures mid-slope or increasing the strength and height of retaining structures constructed at the toe-of-slope could be considered. These alternatives would only improve conditions for the proposed condominium project but not for the off-site properties to the south. The results of the surficial slope stability analysis are included in Appendix D. Setback Criteria Any footings near slopes should satisfy a minimum horizontal setback as indicated in the Uniform Building Code, Chapter 18, Figure 18-1-1. This distance should be measured from the lower leading edge of the footing to the slope face. File NO 2328001 HAmerican Geotechnical, Inc. February 14, 2008 Page 20 6.4 Foundation and Slab Design Parameters The proposed structures can be supported on conventional continuous footings founded in properly compacted fill. Alternatively, a post-tensioned slab/foundation system can be used for support of proposed structures, As previously described, it is recommended that all cut or natural soil areas be over-excavated to a minimum depth of five (5) feet below finished pad elevation and 3 feet below the base of footings. Compacted fill should then be placed and properly compacted to provide relatively uniform soil conditions beneath building foundations and slab areas. The limits of this work should extend a minimum of five (5) feet beyond the aerial extent of proposed improvements (i.e., beyond the limits of the building and appurtenances). Our investigation indicated the presence of expansive soils within the planned development. It is recommended that additional tests be taken at or near pad elevation during grading and/or once the grading is complete, to evaluate the expansivity of the soil used as compacted fill. Recommendations given in the following sections will reflect soils that are non-expansive or have low-expansivity. Because of the large quantities of moderately to highly expansive soils present within the building pad areas, it may not be possible to selectively grade the building pad areas without importing material such that the overall characterization of the soils within five (5) feet of grade are either non-expansive or have low expansivity. As such, foundation and slab systems as well as appurtenant structures may need to be designed in consideration of these conditions. Parameters for higher levels of expansivity or post-tensioned slab design parameters can be provided upon request, Foundation systems should be designed in accordance with the following criteria: Bearing Capacity A. Minimum Embedment Depth (I story) 15 inches (2 story) 18 inches (measured from lowest adjacent compacted soil grade) B. Minimum Width (1 story) , 12 inches (2 story) 15 inches File NO 2328001 HAmerican Geotechnical, Inc. February 14, 2008 Page 21 • Allowable Bearing Pressure for Continuous Footings Founded in Properly Compacted Fill 2,000 psf • Total Loads (including wind or seismic) 2,700 psf • Increased Capacity for Each Additional Foot of Depth Deeper Than Minimum 400 psf • Maximum Value 6,000 psf Resistance To Lateral Loads A. Passive Soil Pressure (equivalent fluid pressure) 200 pcf B. Coefficient of Sliding Friction for Cast Concrete on Compacted Fill 0.4 Footings can be designed to resist lateral loads by using a combination of sliding friction and passive resistance in properly compacted fill. The coefficient of friction should be applied to dead-load forces only. The upper 1.0 feet of passive resistance should be neglected unless pavement or a slab confines the soil. UBC Site Seismic Characteristics The following site seismic parameters were determined in accordance with Section 16, Division IV - Earthquake Design of the Uniform Building Code: Seismic Zone 4 Seismic Zone Factor (Z) 0.40 Soil Profile Type , ...Sc Seismic Source Type B Seismic Coefficient (Ca) 0.40Na Seismic Coefficient (Cv) 0.56Nv Near Source Factor (Na) 1,0 Near Source Factor (Nv) 1.0 It should be noted that these values are considered "minimum design values" as dictated in the Code. RieNO.23280.01 HAmerican Geotechnical, Inc. February 14, 2008 Page 22 6.5 Standard Foundation Recommendations Actual foundation details should be determined by the designer using the criteria presented in Section 6.4, however the following are presented as a guideline to supplement the design process, These recommendations should not preclude structural requirements. 6.5.1 Slab and Footings (Non-Low Expansivity) New footings should have minimum embedment depths as indicated in Section 6.4 reinforced with a minimum of four No. 5 rebar's, two top and two bottom. In addition, it is recommended that a grade beam (similar in size) be installed across garage entrances. New interior and exterior slabs should be at least five inches thick, and reinforced with a minimum of No. 4 rebar at 16 inches on center each way. Sub-slab recommendations are included on Figure 3. As an alternative, a post-tensioned slab/foundation can be utilized. If post-tensioned slabs are used, they should be designed by a structural engineer experienced in the design of post- tensioned elements and should be designed in accordance with the Post-Tensioning Institute (PTI). If additional soil parameters are required for design of post-tensioned slabs, they can be provided upon request. If moderately to very highly expansive soils are encountered within five feet of pad grade once grading is completed, pre-soaking and increased slab designs will be required. Foundation/slab systems for these conditions will typically consist of rigid mat slabs or stiffened post-tensioned slab designs. Concrete Experience and research has shown that concrete with a high water/cement ratio can experience problems such as excessive shrinkage cracking, moisture intrusion, and high vapor emissions, among other things. Generally speaking, the higher the water/cement ratio, the higher the porosity and permeability of the concrete, and the lower the strength. Concrete designed for minimum compressive strengths on the order of 2000-2500 psi can oftentimes have excessive levels of mixing water and correspondingly a high water/cement ratio. Vapor retarder 10-mil min. such as Stego Wrap 10-mil Class A Concrete floor slali1) 4" thick compacted granular2) fill. Clean sand should be avoided. Subgrade consisting of a properly compacted granular soil that is either non-expansive or has low expansivity. (1)High quality concrete with a maximum w/cm ratio of 0.45, designed, placed and cured to produce a low permeability concrete with minimal shrinkage (therefore providing less probability for cracking and curling). Consideration should be given to the use of shrinkage compensating concrete or shrinkage reducing admixtures. Also, maximize the total aggregate content by using clean, well-graded, quality aggregates with the largest practical top-size available. As a general note, all concrete materials, details, placement procedures, and curing should be performed in accordance with ACI specifications and guidelines. (2) Ideally, the fill material should consist of a fine graded, easily compactable soil with a uniform distribution of particle sizes ranging from No. 4 (4.75mm) to the No. 200 (75mm) sieve. Clay should not be used. American Geotechnical, Inc. La Costa Condos Detail for Normal Subgrade Conditions F.N. 23820.01 Figure 3 File NO 2328001 IlAmerican Geotechnical, Inc. February 14, 2008 Page 23 Consideration should be given to using the lowest possible water/cement ratio while still maintaining workability. If necessary, water reducing agents can be used to increase workability. Because of the high levels of sulfate present on-site, it is recommended that concrete used for footings and slab areas conform to the 1997 UBC Table 19-A-4 for maximum water/cement ratio and other concrete design elements. All steel and concrete materials, details, placement procedures, and curing should be performed strictly in accordance with ACI specifications and guidelines. The slab design by the structural engineer and/or architect should consider shrinkage of the concrete to limit cracking to the slab and overlying floor coverings. 6.5.2 Appurtenant Structures The same guidelines for slab and footings would also pertain to design and construction of appurtenant structures; with the exception that exterior flatwork does not usually necessitate the use of a moisture barrier. However, the recommendations for slab thickness and reinforcement for exterior flatwork still pertain to help reduce the potential for cracking and separation, Also proper jointing should be used to control cracking. The contractor should take care in coordinating joint spacing, steel lay-out and doweling as needed. Joint spacing should not exceed 12-feet or 1.25 times the narrow width (i.e. a walkway) which ever is less. Minimum 3/8-inch expansion joint material should be placed wherever new flatwork adjoins existing concrete, foundations, and/or retaining walls. As with interior concrete, all steel and concrete materials, details, placement procedures and curing should be performed strictly in accordance with ACI specifications and guidelines. Special detailing may be necessary to limit unsightly cracking at structural interfaces, such as between foundations and adjacent slabs. Appurtenant structures placed near slope tops could creep over time in response to slope movement. Appurtenant structures should be kept as far away from slope tops as possible. Special detailing can be provided to help minimize the effects of slope influence. This might include structurally tying exterior slabs to the foundation and/or providing a thicker, heavily reinforced section. The project architect and/or structural engineer should develop the actual details. File NO 2328001 HAiTierican Geotechnical, Inc. February 14,2008 Page 24 If moderately to very highly expansive soils are present beneath appurtenances, enhanced designs should be provided to limit potential distress. Because of the substantial pressures that expansive soils can exert, it is not possible to prevent flatwork from experiencing differential movement (uplift during swelling and dropping during shrinkage) when exposed to changes in moisture content. As such, enhanced drainage measures and special detailing and reinforcing should be provided to limit potential damage. 6.5.3 Reinforcement Placement Care should be taken when placing foundation and slab reinforcement. Placement details should be in conformance with ACI specifications. Unless otherwise specified by the structural engineer, continuous footing reinforcement should be placed in the upper and lower 1 /3 portions of the foundation's sections. The bottom foundation steel should not be closer than three (3) inches to the underlying excavation. Slab reinforcement should be placed in a positive fashion between the midpoint and upper 1 /3 portion of the slab section. "Lifting" slab steel into place following concrete placement is not recommended. 6.6 Retaining Wall Design Criteria Where retaining walls are planned, they should be designed utilizing the following design criteria: Restrained Walls (level backfill): At-RestSoil Pressure 70pcf e.f.p. Passive Soil Resistance 200 pcf e.f.p. Cantilever Walls (level backfill): Active Soil Pressure (level backfill) 40-pcf e.f.p. (2:1 sloping backfill) 75 pcf e.f.p. Passive Soil Resistance 200 pcf e.f.p. In order for these soil design parameters to be valid, all planned retaining walls should be properly designed and detailed. All walls should be provided an adequate backdrain system and a clean, coarse grained, non-expansive backfill for a width of at least half the height of the retaining wall for level backfill conditions. File NO 2328001 IIAmerican Geotechnical, Inc. February 14, 2008 Page 25 For ascending slopes that impose an additional surcharge, the minimum width of compacted granular backfill should be increased to a value equivalent to the height of the wall, as a minimum. Increased soil pressures should be used for retaining walls with sloping backfill conditions, Additional parameters can be provided upon request. All retaining walls should be waterproofed from above the highest point of earth retained to the heel of the foundation, The architect should provide details for waterproofing including termination details and provisions for protecting the waterproofing. Each retaining wall should be provided with an appropriate backdrain system designed by the project architect or civil engineer. It is recommended that the backdrain system extend to the heel of the foundation, and at least one (1) foot below interior slab elevation (where applicable). Water collected in the backdrain system should ideally be recovered in a perforated PVC plastic pipe (perforations down) and directed to a suitable disposal area at 1-2 percent gradient unless otherwise specified by the project civil engineer. Retaining wall backfill should be placed in thin lifts (6-8 inches) and compacted by mechanical means. Care should be taken not to utilize heavy compaction equipment in close proximity to the walls to help reduce the possibility of damage to the wall and an increase in the above recommended earth pressures. 6.7 Preliminary Pavement Design Based on our experience on similar projects, with similar soil conditions, the pavement section given in Table 3 can be used for determining preliminary cost estimates. A Traffic Index (Tl) of 5.0 for light traffic and an R-Value less than 10 was assumed for the on-site roadways. TABLE 3 - PAVEMENT DESIGN Tl 5,0 Asphalt Concrete (in) 3 Class 2 Aggregate Base (in) 10 The aggregate base (AB) and upper 12 inches of subgrade should be compacted to 95% percent of the maximum dry density as determined by ASTM D1557, File NO 2328001 19American Geotechnical, Inc. February 14, 2008 Page 26 All fill beneath the subgrade (including trench backfills) should be compacted to a minimum of 90% percent of the maximum dry density per ASTM D-l 557. Our firm should observe and test the compaction of subgrade and base material. Final pavement design can be provided once rough grading is completed and near surface soils are tested, For higher impact areas such as large trash areas, we recommend at least 8 inches of reinforced Portland cement concrete (PCC) over 4 inches of Class 2 aggregate base. Proper reinforcing and crack-control jointing should be provided as designed by the project structural engineer. 6.8 Site Drainage Proper surface drainage should be incorporated into the design for the proposed project. Because of potential problems associated with poor drainage conditions, proper surface drainage should be maintained at all times. As a minimum, the following standard drainage guidelines are recommended and should be considered by the builder/developer and civil engineer during final plan preparation: A, Roof drains should be installed on all structures and tied via a "tight line" to a drain system that empties to a storm drain, terrace drain or other suitable disposal area. B, Surface water should flow away from structures and slopes and be directed to suitable (maintained) disposal systems such as yard drains, drainage swales, street gutters, etc. Three (3) to five (5) percent drainage directed away from structures is recommended. Planter areas adjacent the foundations are not recommended, unless the plants are self- contained with appropriate drainage outlets (i.e., drainage outlets tied via a "tight line" to a yard drain system), C, No drains should be allowed to empty adjacent foundations or over slopes, D, PVC Schedule 40 or equivalent is preferred for yard drains, A corrugated plastic yard drain is not recommended. File NO 2328001 H American Geotechnlcal, Inc. February 14, 2008 Page 27 6.9 Utilities It is not recommended that utilities be planned below a 1:1 projection extending down from the outer edge of foundations, Footings should be deepened to satisfy the foregoing recommendation. Backfill for all utilities should be placed by mechanical compaction methods. Flooding and/or jetting of utility or other trench backfill are not recommended. 6.10 Corrosivity With respect to buried piping, it is considered good construction practice to provide corrosion protection by means of a suitable coating. Placing pressure-plumbing overhead instead of under slabs is desirable. Laboratory tests performed on soil obtained from the site indicate that concrete should be designed in accordance with the "Severe" category of Table 19-A-4 of the 1997 UBC. Test results also indicate a "high" corrosion potential to buried metals. Recommendations should be provided by the project designers to address possible problems related to these findings, 6.11 Geotechnical Services During Construction A representative of this office should be on hand during construction to provide observation and testing services. As previously recommended, our representatives should be on site full- time during grading, Full-time monitoring during excavations related to remedial grading is also recommended and should be carried out in accordance with the accompanying report, We recommend providing observation of all foundation excavations prior to the placement of forms, reinforcement or concrete, Furthermore, it is recommended that our office be requested to review the slab subgrade areas and perform any necessary testing prior to the placement of concrete. 6.12 Plan Review When final plans are available, they should be forwarded to our office for review and comment and/or signature indicating compliance with the intentions of the recommendations contained in this report. If any of the other design professionals or construction members have any questions regarding the site geotechnical conditions or the recommendations of this report, our office should be contacted, File NO 2328001 19 American Geotechnical, Inc. February 14, 2008 Page 28 7.0 OTHER CONSIDERATIONS 7.1 Project Safety The contractor is the party responsible for providing a safe site. American Geotechnical will not direct the contractor's operations and cannot be responsible for the safety of personnel other than our own representatives on-site. The contractor should notify the owner if he is aware of, and/or anticipates, unsafe conditions. At the time of construction, if the geotechnical consultant considers conditions to be unsafe, the contractor, as well as the owner's representative, will be notified. 8.0 REMARKS Only a small portion of subsurface conditions have been reviewed and evaluated. Conclusions, recommendations, and/or other information contained in this report are based upon the assumption that subsurface conditions do not vary appreciably between observation points. Although no significant variation is anticipated, it must be recognized that variations can occur. This report has been prepared for the sole use and benefit of our client, The intent of the report is to advise our client on geotechnical matters involving the proposed development. It should be understood that the geotechnical consulting provided and the contents of this report are not perfect. Any errors or omissions noted by any party reviewing this report, and/or any other geotechnical aspects of the project, should be reported to this office in a timely fashion. The client is the only party intended by this office to directly receive this advice. The client can only authorize subsequent use of this report. Conclusions and recommendations presented herein are based upon the evaluation of technical information gathered, experience, and professional judgment. Other consultants could arrive at different conclusions and recommendations. Final decisions on matters presented are the responsibility of the client and/or the governing agencies. No warranties in any respect are made as to the performance of the project. ••American Geotechnical, Inc. APPENDIX A - REFERENCES "Soils Investigation, La Costa Views Lot 185, La Costa South Unit No. 1, San Diego County, California," prepared by Benton Engineering, Inc. dated August 23, 1971, (only boring logs were available for review) "Geology of the San Diego Metropolitan Area, California, Bulletin 200," prepared by Michael P. Kennedy, dated 1975. "Simplified Procedures for the Evaluation of Settlements in Sands Due to Earthquake Shaking," Earthquake Engineering Research Center University of California at Berkeley, prepared by Kohji Tokimatsu and Bolton Seed, dated 1984. "Design and Control of Concrete Mixtures," prepared by Portland Cement Association (PCA), dated 1988, reprinted (revised) 1994. "Geology of California," second edition, prepared by Robert M. Morris and Robert W, Webb, dated 1990. "Landslide Hazards in the Northern Part of the San Diego Metropolitan Area, San Diego County, California" California Division Of Mines and Geology, 1995, prepared by Siang S, Tan and Desmond G. Giffen. "Uniform Building Code", prepared by International Conference of Building Officials, dated 1997. "Damage and Distortion Criteria for Residential Slab-on-Grade Structures, ASCE Journal of Performance of Constructed Facilities," prepared by Edred T. Marsh and Scott Thoeny, dated August 1999. "Preliminary Geotechnical Investigation, lot 185, La Costa Avenue South, Unit 1, Carlsbad California, Project No. 4980161-001," prepared by Leighton and Associates, Inc., dated September 24, 1999 "E.Q. Fault," version 3.0, prepared by Thomas F. Blake, dated 2000. "E.Q, Search," version 3.0, prepared by Thomas F. Blake, dated 2000. "Recommended Procedures for Implementation of DMG Special Publication 117 Guidelines for Analyzing and Mitigating Landslide Hazards in California," Published by the Southern California Earthquake Center, dated June, 2002. "Update Preliminary Geotechnical Report, Lot 185, La Costa Avenue South Unit 1, Carlsbad, California," prepared by Leighton and Associates, Inc., dated October 30, 2002. "Remedial Grading Procedures Relative to the Existing Ancient Landslides and North-facing Hillside, La Costa Condominiums, Lot 185 of La Costa South Unit 1, Carlsbad Tract No. 02-28, Carlsbad, California," prepared by Leighton and Associates, dated January 18, 2005, revised October 27, 2006, HAmerican Geotechnical, Inc. <m Ml APPENDIX A - REFERENCES (CONTINUED) "Public Improvement Plans for La Costa Condominiums sheets 1-9," prepared by O'Day Consultants, dated May, 2005. "Grading and Erosion Control Plans for La Costa Condominiums sheets 1-9," prepared by O'Day Consultants," May, 2005. "Preliminary Repair Recommendations, Banich Residence Landslides, 2516 Sacada Circle, Carlsbad, California, " prepared by American Geotechnical Inc., dated October 19, 2006. " Supplemental Repair Recommendations, Banich, Powers, Calso Landslides, 2416 Sacada Circle, Carlsbad, California," prepared by American Geotechnical Inc., dated February 19, 2007. "Grading Plans for Banich, Powers, Calso Landslide Stabilization, 2416 Sacada Circle, Carlsbad, California," prepared by American Geotechnical Inc., dated March 27, 2007. HAmerican Geotechnical, Inc. APPENDIX B - SUBSURFACE LOGS Boring N Project Na Location: Tola Ke Deptf lly wt 0 me: 2416 ._._. 1 FiiPNo 23080.01AGLB-1 Shfifit: Banich c r , "/-M/OPSlHil IJHlH: u/^^/UD ) Sacada Circle (Front of house in the street) FnH natQ. 8/24/06 i: 80.0' Rig Type: 30" dia. truck mounted Est. Surface Elevation: _ ocpn IKO n oc' bucket rig by Larvive Drilling 24C 13C 10 ihs ?5 - 55' Sampled with modified CA )0 Ibs 55 - 85' split spoon Location Profile See Site Plan Depth in Feet o.o -T] 2.0 - 4.0 — 60 ~ 8.0 -E 12.0 — 14.0 — 160 ~ 18.0 -£ 20 0 ~ 22.0 - 24.0 - 26.0 - 28.0 -5 30.0 - 32.0 — 34.0 — 36 0 ~ 38.0 -E 40.0 — 42.0 — 44.0 — 46.0 -E 48.0 -E 50.0 — Sample Type J Blow Count Field Description By: KR Surface Conditions: Subsurface Conditions: ASPHALT CONCRETE 0.0" - 3.0" (Street) 3" minimum and 3 Va" maximum thickness ROAD BASE 3.0" - 7.0" Fine gravelly silty SAND, mottled white, dark gray and tan, slightly moist, dense to very dense, mica flakes and fine gravel size fragments of granitic rocks FILL 7.0" - 1 2.0" Silty SAND, mottled light tan and white, damp to slightly moist, very dense SANTIAGO FORMATION 1 .0' - 7.0' Oxidized silty fine SANDSTONE, mottled light yellow tan and white with orange rust oxidation-stained bedding and nodules, damp to slightly moist, moderately indurated, moderately strong, low angle to near horizontal bedding in upper 5.0', becomes less oxidized white, weakly to moderately indurated, friable, silty fine SANDSTONE below approximately 4.0' 7.0' - 13.0' Massive white to light tan silty SANDSTONE, damp, moderately indurated and strong, some oxidized yellow and yellow-orange laminations that are low angle (less than 10°) with variable strikes (near horizontal) 1 3.0' - 1 6.0' Zone of silty SANDSTONE mottled with abundant orange rust oxidation- staining, grades into oxidized tan sandy SILTSTONE 1 6.0' - 29.0' Slightly sandy SILTSTONE, light tan with orange-rust oxidation stains 1 6.0' - 23.4' Near vertical vein-filled fracture 1 /8 - 1 " wide, rust and black-colored (Fn &Mn oxides) widens with depth where at 20.0' it intercepts oval vug coated with iron and manganese oxides, the vertical vein-filled fracture narrows to approximately 1/8 wide below the void and ends at approximately 23.4' 20.5' - 22.0' Numerous near-horizontal gypsum veins approximately 1/8" wide NOTE: After 20.0' each expert took turns sampling every 5.0' starting with Heatherington at 25.0', Stoney Miller at 30.0', and American Geotechnical at 35.0', etc. 1^1 American ^H Large Bag MB! GeOtechnJCal Ring Sampler FilpNn 23080.01Boring Nn AULb-l Sheet: Project Name- Banich °/'M/nr I ocation- 241 6 Sacada Circle (Front of house in the street) End Dato. 8/24/06 Total Depth: 80.0' RJQ Type: Est. Surface Elevation: Location Profile See Site Plan Depth in Foot 50.0 -i 52.0 - -_ 54.0 - 56.0 -E 58.0 - ~ 60.0 -- 62.0 — - 64.0 — 66.0 - 68.0 - 70.0 -_ 72.0 - 74.0 - 76.0 - 78.0 -E 800 — 82.0 - 84.0 - 86.0 — - 88.0 - 90.0 - 92.0 - = 94.0 — 96.0 —_ 98.0 -E 100.0 -3 Sample Type Blow Count 1 Field Description By: KR Surface Conditions: Subsurface Conditions: @ 23.0' SILTSTONE laminations: N 1 OE/5W, below 20.0' the SILTSTONE is light brown to tan. mottled with closely spaced yellow oxidized laminations with some approximately 1/8" wide gypsum oriented veins approximately parallel to bedding @ 25.8' Several near-horizontal gypsum veins oriented approximately Vi - 3/8" wide @ 26.6' Concretion - elliptical - disc shaped with very hard cemented core encased with soft highly oxidized orange and black stained SILTSTONE beds 26.0' - 28.0' Moist cuttings, below 26.6' laminations are oxidized orange-rust @ 29.0' Grades into light tan silty SANDSTONE, moderately indurated and strong, moist with orange oxidation stains @ 34.0' Bedding: N15E/13SW, cuttings are moderately indurated, moderately strong white silty fine SANDSTONE, damp with paper-thin tan to light brown clay coated laminations spaced W apart at near-horizontal orientation 35.0' - 36.0' White to light gray silty fine SANDSTONE, well indurated and strong, mottled with some orange to brown oxidation stains, approximately %" thick layer of orange oxidized silty very fine SANDSTONE in sample tip @40.0' Bedding: N18E/9SE @45.4' Bedding: N31E/7SE @ 46.0' Cemented zone approximately 6.0" thick continuous around borehole 46.0' - 49.0' Intensely oxidized 46.0' - 47.0' Cuttings are orange to brown, intensely oxidized, moist, silty SANDSTONE with fragments of very hard concreted SANDSTONE @ 49.0' Seepage along approximately '/•> wide sub horizontal gypsum vein intensely oxidized, hard, well-cemented zone 49.0' - 54.8' Becomes slightly sandy SILTSTONE, light brown mottled with yellow and orange oxidized laminations, slightly moist to moist 54.8' - 55.6' N34E/4W, very hard cemented zone of concreted smoke to gray SILTSTONE with abundant tiny white bi-valve fossil shells, very difficult drilling underlain with approximately 1 .0' layer of orange oxidized very fine SANDSTONE Mm American Hi Large Bag EOH GeotechniCQl, Inc. yn Ring Sampler Boring N Project Na Location: Total Deptf n ne: 2416 .-._ 1 FilPMn 23080.01AGLB-1 Sheet: Banich c~. i r-i i n/o/i /ORSlnrl mle: o/^4/UD ) Sacada Circle (Front of house in the street) FnH nato. 8/24/06 1: 80.0' Rjn Type: Est. Surface Elevation: Location Profile See Site Plan Depth in Feet 50.0 -, 52.0 - 54.0 — 56.0 - 58.0 - 60.0 — 62.0 — 64.0 -^ 66.0 — 68.0 - 70.0 -= 72.0 — 74.0 - 76.0 - 78.0 -E 80.0 — 82.0 - 84.0 — 86.0 - 88.0 - 90.0 - 92.0 - 94.0 - 96.0 -E 98.0 ^ 100.0 — Sample Type Blow Count Field Description By: KR Surface Conditions: Subsurface Conditions: @56.5' Dark smoke gray silty very fine Sandstone, moderately indurated and strong @ 60.0' Drilling suspended at 5:00 to be resumed at 8:00 the following day, drilling resumed at 8:00, approximately 4.0" of water has accumulated overnight in bottom of hole @ 60.4' Contact between smoke to gray SANDSTONE above and dark gray mudstone below: N12E/5W 60.4' - 76.0' Very dark gray to green mudstone or SILTSTONE hard and well indurated but with many low and high angle polished shears (tectonic shears) at various orientations, number of shears decreases with depth DELMAR FORMATION 65.0' - 65.85' Mudstone, dark gray to green, damp, well indurated, hard and strong, non -oxidized subparallel paper thin polished surfaces (tectonic shear?) with out gouge or breccia halo about 3/8 apart that dip at approximately 21° and 55° @ 76.0' Downhole log terminated, approximately 0.5' - 1 .0' of water accumulated in bottom of borehole, the hole was backfilled with a lean concrete to sandslurry delivered by Superior Mix with 2 sack sand/yd3 @ 80.0' Boring terminated, no caving, seepage at 49.0' KM American • Large Bag MB! Geotechnical Ring Sampler Boring N Project Na Location: Total Deptf Kelly v n. me: On si ,_|R_ FilPNn 23080.01AGLB-2 Sheet: Banich o/->r)/npSlHrl Dnle: o/Zy/Uo Dpe within landslide graben below 2416 Sacada Circle Fnrl nato. 8/29/06 v. 37.0' Rig Type: 24" limited access Est. Surface Elevation: * onni^ 1 1Q> bucket riq by Barbell Drilling 4<sn ihs VR - 40' Sampled with modified CA split spoon Location Profile See Site Plan Depth in Feet 0.0 — i 2.0 - 4.0 - 6.0 - 8.0 -E 10.0 — 12.0 - 14.0 ~ 16.0 — 18.0 -E 20 0 ~ 22.0 — 24.0 — °6 0 ~ 28.0 -E 30.0 - 32.0 — 34.0 — 36.0 — 38.0 —_ 40.0 - 42.0 — 44.0 — 46.0 ^ 48.0 -E 50.0 — Sample Type •Bt = •mof"- •»-""*" Blow Count Field Description By: KR Surface Conditions: Subsurface Conditions: ANCIENT LANDSLIDE DEBRIS7/FILL 0.0' - 3.5' Silty SAND with gravel, mottled white to light gray with orange to brown oxidation stains, moist 3.5' - 5.75' Silty SANDSTONE, highly weathered and oxidized, disturbed relict bedding 5.75' - 7.0' SILTSTONE, medium to dark brown, firm to medium stiff, moist to very moist, abundant roots, grades downward into weathered Delmar Formation mudstone? Several subparallel polished clay seams in weathered siltstone - possible ancient landslide shears RECENT LANDSLIDE DEBRIS/INTENSELY FRACTURED DELMAR FORMATION 7.0' - 22.5' MUDSTONE, medium dark gray green, highly fractured (fresh), closely spaced with numerous polished surfaces in various orientations, light oxidation on some fractures but many are not oxidized, fractures are discontinuous except for some as noted below @ 12.75' Paper thin fracture old continuous around borehole, oxidized and with rootlets, orientation = N10E/26W 1 5.0' - 20.0' Cobble size concretions in cuttings |^| American •• Large Bag MSl Geotechnical Ring Sampler Borinq N•*j 0. .r.D _ File No 23080.01AGLB-2 f-* 1 .>>neet: Project Nar-pp. DaniCh n/nn/r^Start Date: o/zy/Uo Location: On slope within landslide graben below 2416 Sacada Circle End Date- 8/29/06 Total Depth: 37.0' Riq Type: Est. Surface Elevation:l xj j i Location Profile See Site Plan Depth in Feet 0.0 -q 2.0 — A nT-.U — 6.0 - 8.0 - - 10.0 — 12.0 — 14.0 — 16.0 — 18.0 -E 20,0 -EE 22.0 — 24.0 — 26.0 -E 28.0 -E 30.0 — 32.0 — : 34.0 — 36.0 - 38.0 — 40.0 — 42.0 - 44.0 - 46.0 -E 48.0 -E 50.0 — Sample Type Blow Count Field Description By: KR Surface Conditions: Subsurface Conditions: 22.5' Possible base of landslide, no distinct basal shear, several coalescing. lightly oxidized polished shears N80W/13N, bottom of zone of closely spaced fractures, becomes relatively intact, hard SILTSTONE below with fewer and more widely spaced fractures DELMAR FORMATION 22.5' - 25.25' Hard intact relatively unfractured SILTSTONE with some concretions @ ~ 24.0' Drilling becomes difficult, 10" diameter bucket core installed on rig, core cuttings are medium to dark green SILTSTONE, well indurated and strong, with very few fractures, coated with light oxidation @ 25.25' Seepage from within fractured, very hard cemented zone, approximately 3-4" thick with orientation N50W/4N 25.25' - 34.0' Delmar formation mudstone, dark gray-green some fractures coated with light oxidation, at various orientations @ 30.0' Drill cuttings are Delmar formation mudstone, well indurated, moderately strong, damp to slightly moist, medium to dark green, fractured with numerous polished surfaces with various orientations (tectonic?) @ 34.0' Downhole log terminated - bottom of hole filled with sidewall spoils from downhole logging @ 35.0' Drill cuttings change to light tan, sandy and clayey SILTSTONE @ 37.0' Drilling termindated. Some seepage into bottom of boring KMj American • Large Bag M9 Geotechnical P""! Ring Sampler Test Pit l\ Project Narr Location: Total Depth In AGTP - 1 p. Banich Residence 2416Sacada Circle Fi|flNn 23080.01 °tnrt n-itp- 8/03/06 mnn**, 8/03/06 4.8' Rjg Type: Hand Excavation Est. Surface Elevation: Location See Site Plan Depth in Feet o.o - i.o -E 2.0 -E 3.0 -E 4.0 -= 5.0 -E 6.0 -E 7.0 ~- 8.0 -E 9.0 -E 10.0 -E 11.0 -E 12.0 -. 13.0 -E 14.0 -E 15.0 -E 16.0 -E 17.0 -E 18.0 -E 19.0 -E 20.0 -3 Sample Type Intact Bulk Field Profile Description By: KR Surface Conditions: Subsurface Conditions: FILL 0.0' - 1 .2' Silty SAND mottled with pebble to gravel size fragments of white, yellow and orange silty sand, medium dense to very dense, some roots 1 .2' - 1 .5' 1 -3" thick dipping layer of dense to very dense silty SAND with abundant pebble to gravel size fragments of yellow, white and orange sandstone and green siltstone and mudstone, dips downslope approximately 36° 1 .5' - 4.8' Silty SAND with pebble to gravel size fragments of green formation claystone, tan, very moist, medium dense to loose, rootlets TUBES® 2.5' -3.8' @ 4.0' -4.8' LB@2.5'-4.0' a American Geotechnical Test Projec Locatic Total C Pit IS t Narr )n: )epth In AGTP - 2 fi: Banich Residence 241 6 Sacada Circle Fii^Nn. 23080.01 °tirt Date- 8/04/06 PnHn^. 8/04/06 5.0' Rjg Type: Hand Excavation Est. Surface Elevation:~ " ' Location See Site Plan Depth in Feet o.o - i.o -E 2.0 -E 3.0 -E 4.0 -E 5.0 -E 6.0 -E 7.0 -^ 8.0 -E 9.0 -E 10.0 -E 11.0 -E 12.0 -E 13.0 -E 14.0 —_ 15.0 -E 16.0 -E 17.0 -E 18.0 -E 19.0 -E 20.0 -3 Sample Type Intact Bulk Field Profile Description By: KR Surface Conditions: Subsurface Conditions: RECENT LANDSLIDE DEBRIS 0.0' - 1 .6' Recent landslide debris, light tan silty SAND, mottled with pebble and small gravel size fragments of green clayey SILTSTONE Formation @ 1 .6' Basal shear dips downslope at 27° approximately Vz' to 1 " thick mottled zone of smeared green clay and brown and white sand FILL 1 .6' - 5.0' Gravelly and clayey SILT with light green and dark green round sand to gravel size fragments of Formation clayey SILTSTONE, green, moist to very moist, soft to firm, roots, mottled with orange oxidized sand grains TUBES @ 2.0'-2.9' LB @ 2.0' - 3.0' KM American Mfil Geotechnical Test Pit Nn AGTP-3 File No. 23080.01 Project Name: Banich Residence Location: 2416 Sacada Circle Start Date: 8/04/06 8/04/06End Date: Total Depth: 2.4' Rig Type: Hand Excavation Est. Surface Elevation:. Location Profile See Site Plan Depth in Feet Sample Type Intact Bulk Field Description By: KR Surface Conditions: Subsurface Conditions: o.o — 1.0 -E 2.0 -E 3.0 -E 4.0 -E 5.0 -E 6.0 -E 7.0 -E 8.0 -E 9.0 -E 10.0 -E 11.0 -E 12.0 -E 13.0 —_ 14.0 —_ 15.0 -E 16.0 -E 17.0 -E 18.0 -E 19.0 20.0 -3 FILL 0.0'-1.7' 1.7'-2.4' Silty SAND with pebble and gravel size fragments of white SANDSTONE and green SILTSTONE, slightly moist to moist, dense to very dense, roots Green gravelly and clayey SILT mixed with medium brown silty sand, moist, stiff to very stiff with roots and some cobbles TUBES @ 1.5' - 2.4' American Geotechnical GEOTECHNICAL BORING LOG KEY Date, Project Drilling Co. _ Hole Diameter KEY TO BORING LOG GRAPHICS Sheet 1 of Project No. "type of Rig _ Drive Weight Drop in. pievatlonTopofHole +/- ft. Ref. or Datum levation 1(feet) 1HI frj! o — •• 15" o F '//// vffit A A AA A A AA A A [ J II r\ ' 2§ #•'•: ***•*•' !•'*"*•"-'" ! "•" •*. "%&> u ^^ ^^^+? V Co- . '• *t ^ $%? in l^*x s N_N J V << «4 t^t- ///$•//> i "RBI! jfl— 6^00 6* (A 03 fe O. ndicateSPTSample IndicateTCalSample k 4- o dcateswatertime of MoistureContent CO |^gro\ndaval atdrfihg • ••• * CL CH OL-OH ML MH CL-ML ML-SM CL-SC SC-SM SW SP SM sc GW GP GM GC GEOTECHNICAL DESCRIPTION Logged By Sampled By Inorganic clay of low to medium plasticity; gravelly clay; sandy day; silty clay, leanclay Inorganic clay of high plasticity; fat clay Organic clay, silt or silty clay-clayey silt mixtures Inorganic silt; very fine sand; silty or clayey fine sand; clayey silt with low plasticity Inorganic silt; diatomaceous fine sandy or silty soils* elastic silt Low plasticity clay to silt mixture Sandy silt to silty sand mixture Sandy day to clayey sand mixture Clayey sand to silty sand mixture Well graded sand; gravelly sand, little or no fines Poorly graded sand; gravelly sand, little or no fines Silty sand; poorly graded sand-silt mixture Clayey sand; poorly graded sand-day mixture Well graded gravel; gravel-sand mixture, little or no fines Poorly graded gravel; gravel-sand mixture, little or no fines Silty gravel; gravel-sand-silt mixture Clayey gravel; gravel-sand-clay mixture Sandstone Siltstone daystone Breccia (angular gravel and cobbles or matrix-supported conglomerate) Conglomerate (rounded gravel and cobble, clast-supported) Igneous granitic or granitic type rock Metavolcanic or metamorphic rock Artificial or man-made fill AsphalUc concrete Portland Cement Concrete 505AC1V77)LEIGHTON & ASSOCIATES Date Project Drilling Co. _ Hole Diameter 6-22-98 GEOTECHNICAL BORING LOG B-l Calso, Ltd. WestHazmat Sheet 1 of 1 Project No. 980161-001 Type of Rig CME85 Sin.Drive Weight 140 pounds Drop 30 in. Elevation Top of Hole +/- 116 ft. Ref. or Datum Mean Sea Level §. 58fcin 115 110 105 100 ne. 90- £~ii o — - - 5 — 10 — - 15 — - 20 — - 25 — - 10 — u*A '!•-':[.': ' / " ^%$1 // '•• •1! •/i. V : *•/ % P% %V. /•/ wi o 011& Bag-1 @0'-5' 1 2 3 4 5 §8 45 21 35 120 110 3)-t- 5*0 °£ 3»~ h 99.0 105.2 ^N2- •H+: 5"c 3 20.1 15.6 *>; o) CO SM CL/SC SM GEOTECHNICAL DESCRIPTION Logged By JD Sampled By JD ARTIFICIAL FBA @ 0': Brown, dry-damp, loose, silty fine SAND, with roots and grasses @ 1.5': Dark brown, red-brown, light brown, and gray, mixed, medium/stiff damp, sandy CLAY, clayey SAND @2.5': Same as above, dense @ 5': Gray-brown, light brown and olive-brown, mixed, damp, medium dense/stiff, sandy CLAY/ clayey SAND - @ 10': As above, medium dense/stiff - TERTIARY DELMAR FORMATION @ 13': Blue-green, damp, very dense, silty fine SANDSTONE @ 15.5': Light brown, damp, very dense, silty fine to medium SANDSTONE @20': As above, very dense Total Depth = 21 Feet No Ground Water Encountered at Time of Drilling Boring Backfilled with Soil Cuttings on June 22, 1998 . - - 505AC11/77)LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG B-2 1 Date 6-22-98 Project Drilling Co. Hole Diameter 8 in. Elevation Top of Hole +/- 114 i^ «">«S.0>v_^ UJ 110 105 100 95 90- 85- ^ £«a,*a£ o — 5 — 10 — 15 20 — 25 — — - in — u -CC9ao CD /"/•/yxxxx n %%; n IS n H H i! ^%'///,w wfc U)Q)•t-Oz o 01 Q. ien 6 7 8 9 10 11 -ii• : 1 : ! i [ - - Sheet 1 of 2 Calso, Ltd. Project No. 980161-001 West Hazmat Type of Rig CME 85 Drive Weight 140 pounds Drop 30 in. ft. Ref. or Datum Mean Sea Level +- 00 — , 0_ 45 50 35 60 60 80 3) cV Q Q. 3) a 100.0 101.8 104.7 . ^o,* ^£! 20.6 19.9 20.1 . 22•>•• * CO ... * cov sc CL SC GEOTECHNICAL DESCRIPTION Logged By JD Sampled By JD ARTIFICIAL FILL @0': Brown, dry, loose-medium dense, clayey SAND with roots and grasses @ 2': Dark brown, olive-brown, light brown and red-brown, damp, medium dense/dense, clayey SAND - @ 5': As above, dense • @ 10': Dark brown, and olive-brown, damp, medium dense, clayey SAND - @ 15': As above, dense • @ 20': As above, dense . @ 25': Black and dark green, damp, stiff, sandy CLAY with blackened plantfragments, roots QUATERNARY COLLUVIUM @ 27': Brown and red-brown, with light brown, gray and olive fragments, damp, dense clayey SAND • 505« n/77) LEIGHTON & ASSOCIATES I I Date Project Drilling Co. Hole Diameter 6-22-98, GEOTECHNICAL BORING LOG B-2 Calso, Ltd. West Hazmat Sheet 2 of 2 Project No. 980161-001 Type of Rig CME 85 Sin.Drive Weight 140 pounds Drop 30 in. Elevation Top of Hole +/-__114_ ft. Ref. or Datum Mean Sea Level 1 evat i on 1Cfeet) 1UJ 80 75 70 65 60- 55- f| 30 — — 35 — - 40 — - 45 — - 50 — - - 55 — fin — o 1 %, <x £ ^ '-: : :-; 0).0_l X 'v'1't, X X X / X / X X X xX Xx" X X X (001 (0 0. V) 12 1 13 I 14 I 15 16 1 4- in O 3 ° n j 140 115 I 100 95 1 100/3" 31 c£(U U °-Sr 3> a 105.2 || EO 19.8 «_ * C/J O)^ sc SIvi/SC SM GEOTECHNICAL DESCRIPTION Logged By JD Sampled By JD @ 30': Brown and red-brown, with gray and olive fragments, damp, very dense, clayey SAND _ @ 35': As above, very dense - @ 40': As above, dense TERTIARY DELMAR FORMATION @ 43': Light greenish tan with maroon fissures, damp, very dense, clayey/silty SAND @45': As above, very dense @ 47': Light tan with red-brown fractures, damp, very dense, silty fine to medium SANDSTONE - @ 50': As above, very dense Total Depth = 51 Feet No Ground Water Encountered at Time of Drilling Boring Backfilled with Soil Cuttings on June 22, 1998 • - - 505AC11/77)LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG B-3 Date Project 6-22-98 Sheet ct ing Co. Diameter 8 in. ition Top of Hole +/- 109 Calso, Ltd. West Hazmat Drive Weight ft. Ref. or Datum Project No. Type of Rig 140 pounds Mean Sea Level 980161-001 CME85 Drop 30 in. °~ 58fo UJ 105 100 95 90 85- 80- II 0 — 5 — - 10 — - 15 — - 20 — - 25 — - 0 I :-; 0)o /•'/•/////. i>JX \ ^ % I/I91+•O »0 (V Q. W Bag-2 @0'-3' 17 18 19 •*- ?ii — ~ ^ 50 100 110 3 fll o °<5 Q £is &*- oU ""w5 05 0) SM/SC SM/SC GEOTECHNICAL DESCRIPTION Logged By JD Sampled By JD ARTIFICIAL FILL @ 0': Light green-tan, damp, loose, silty/clayey fine SAND, with roots and grasses @ 2': Same as above, dense, no roots/weeds TERTIARY DELMAR FORMATION @ 5': Light green-tan, damp, very dense, silty/clayey SANDSTONE - @ 10': As above, very dense Total Depth = 1 1 Feet No Ground Water Encountered at Time of Drilling Boring Backfilled with Soil Cuttings on June 22, 1998 - - - - - - - 505AC11/77)LEIGHTON & ASSOCIATES I GEOTECHNICAL BORING LOG B-4 Date Projec Drilli. Hole Eleva E 1 evat i on 1(feet) 1115- 110- 105- 100- 95- 90- ss- 6-22-98 ••t QgCO. Diamet tion To II o — 5 — 10 — 15 — 20 — 25 — in — Calso, Ltd. Sheet 1 of 1 Project No. 980161-001 West Hazmat Type of Rig CME 85 er 8 in. p of Hole +/- 115 ft.Graph i c 1Log 1i 014-o * Q 01 "o. aCO Bag-3 1 7 21 I 22 j L §8 5fca. 80 140 90 J Drive Weigh Ref. or Data &,->,C4-01 Oa a a Mo i stureContent (*>t 140 pounds Drop 30 in. m Mean Sea Level C/) O r™/CO sc SM/SC SM/ML GEOTECHNICAL DESCRIPTION Logged By JD Sampled By JD ARTIFICIAL FILL @ 0': Light greenish brown, damp, loose clayey fine SAND with roots and grasses @ 2': Light green-tan, damp, dense, silty/clayey fine SAND TERTIARY DELMAR FORMATION @ 5': Light green-tan, damp, very dense, silty fine SANDSTONE/sandySILTSTONE @ 8': As above @ 10': As above, very dense Total Depth = 11 Feet No Ground Water Encountered at Time of Drilling Boring Backfilled with Soil Cuttings on June 22, 1998 505AC11/77)LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG B-5 Date Project 6-22-98 ct ing Co. Diameter ition Top of Hole Sin. +/- 123 Calso, Ltd. West Hazmat Drive Weight ft. Ref. or Datum Project No. Type of Rig 140 pounds Mean Sea Level 980161-001 CME85 Drop 30 in. °~ 5! fo Ul 120- 115- 110- 105- 100- 95- £$Otf 0 — - - - e _1J,_ - 10 — - 15 — - 20 — - 25 — - U a2o \\ ! /•'/' Yt fr/ '& tf?' 1 1 ^ w I * at i 23 24 25 - , } - , - - - - 4- U)° 3 ° 70 80 110 4- 85 °v& a 2S3+£ u • "S <8^ SM/SC SM/SC GEOTECHNICAL DESCRIPTION Logged By JD Sampled By JD ARTIFICIAL FILL @ 0': Light greenish tan, damp, loose, silty /clayey SAND @2': As above, dense - TERTIARY DELMAR FORMATION @ 5': Light green tan, damp, dense, silty /clayey SANDSTONE, with dark green slickensides - @ 10': As above, very dense with slickensides Total Depth = 11 Feet No Ground Water Encountered at Time of Drilling Boring Backfilled with Soil Cuttings on June 22, 1998 - - - - - - 505A<11/77)LEIGHTON & ASSOCIATES Date Project . Drilling Co. Hole Diameter 6-22-98 GEOTECHNICAL BORING LOG B-6 Calso, Ltd. West Hazmat Sheet 1 of 2 Project No. 980161-001 Type of Rig CME85 Sin.Drive Weight 140 pounds Drop 30 in. Elevation Top of Hole +/- 121 ft. Ref. or Datum Mean Sea Level 1 evat i on(feet)UJ 120- 115- 110- 105- 100- 95- ££ a™ 0 — ~~" - 5 — 10 — - 15 — - 20 — 25 — - 10 u 1C£ •.' 'sy- ^ IP \ % // § '/'/ / \ \i ^^/. \ ^\t ^ •'.- X/ X X X X X /. X X X. X X X X X> X X X. X x X X/ X/ X X X X X X X X X X X X / X X/ X X X X X X X/ X/ X in0)i o (Uifflen Bag-4 1 @0'-3'L 26 1 27 1 28 j 29 j 30 j 31 j! ji Q. 76 55 65 60 70 70 3> •H tfl^.CM-01 uQQ.^/•Jl h 99.7 97.1 96.3 ^S u 20.3 20.5 23.3 ^ u°!WJ* CO SM/SC CL SM GEOTECHNICAL DESCRIPTION Logged By JD Sampled BY JD ARTIFICIAL FILL @ 0': Olive-brown, dry, loose, clayey SAND, with roots and weeds @ 1.5': Dark brown, red-brown and olive-brown, mixed, damp, dense, silty/clayey fine SAND - @ 5': As above, dense @ 10': As above, dense - @ 14': Olive-brown and dark brown, damp, moist, sandy CLAY @ 15': As above, very stiff - @ 20': As above, very stiff - @ 25': As above, very stiff - TERTIARY DELMAR FORMATION @ 27': Light greenish tan, damp, very dense, silty fine to medium SANDSTONE 505AC11/77)LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG B-6 6-22-98 Sheet 1J "H Project Drilling Co. Hole Diameter 8 in. F.levationTopofHole +/- 121 Calso, Ltd. West Hazmat Drive Weight ft. Ref. or Datum Project No. Type of Rig 140 pounds Mean Sea Level 980161-001 CME85 Drop 30 in.E 1 evat i on 1(feet) |90 85 80 75 70- 65- ISte 30 — 35 — 40 — 45 — 50 — - 55 — fin — u I»IB-J O ;.;'••-Notes*£ 01 Q. 1 32 §1rt Ll» mfco_ 100 3»•t- g?££\^i Mo i stureContent <*> |«*~8» 0^_w 0 =(0~ SM GEOTECHNICAL DESCRIPTION Logged By JD Sampled By JD @ 30': light greenish tan, damp, very dense, silty fine to medium SANDSTONE Total Depth = 31 Feet No Ground Water Encountered at Time of Drilling Boring Backfilled with Soil Cuttings on June 22, 1998 . - - - - - - - - - ** 505A(11/77)LEIGHTON & ASSOCIATES Date Project Drilling Co. _ Hole Diameter 6-22-98 GEOTECHNICAL BORING LOG B-7 Calso, Ltd. West Hazmat Sheet 1 of 1 Project No. 980161-001 Type of Rig CME8S Sin.Drive Weight 140 pounds Elevation Top of Hole +/- 112 ft. Ref. or Datum Mean Sea Level Drop 30 in. §,1 evat i(feetLU 110 105 100 95 90- 85- 8 o — - - 5 — - — 10 — - 15 — - 20 — - 25 — _ - 10 0 aa f* k §' , I ^ _i '/'/• '/fa ///y % I %, '% % •• \l <ui *o +• Q) §U- t~ fflfc •"• QJ Bag-5 1 ®0'-3' I L u33 I 44 34 I 70 H | 35 I 50 M 0 36 I 80 I 37 I 71 | 38 I 90 . - +- C4- °| h 104.1 99.2 95.8 101.6 <u£c.ft&r3 16.2 22.0 25.3 22.0 • ^J* o ^^0) SM/SC CL SM GEOTECHNICAL DESCRIPTION Logged By JD Sampled BY JD ARTIFICIAL FILL @ 0': Light olive-brown, damp, loose, silly/clayey fine to medium SAND @ 2': As above, dense, no roots or grasses, mixed light olive with gray, red-brown and dark brown @ 5': As above, very dense - . @ 10': As above, very dense - @ 13': Dark brown, red-brown and olive-brown, damp, stiff, sandy CLAY @ 15": As above, very stiff - @20': As above, very stiff - TERTIARY DELMAR FORMATION @25': Light greenish tan, damp, very dense, silty SANDSTONE Total Depth = 26 Feet No Ground Water Encountered at Time of Drilling Boring Backfilled with Soil Cuttings on June 22, 1998 * 505AC11/77)LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG LB-1 Date Project Hole 7-13-98 't no C.n. "1 ^ 1MDiflfneter A* **•• Hnn Ton of Hole 129 ft. CALSO Ltd. San Diego Drilling Drive Weight 0-30'. Ref. or Datum Sheet 1 of 1 Project No. 980161-001 Type of Rig Bucket 5,000 Ibs.; 30-60', 389 Ibs.: 60-90'. 2,446 Ibs. Drop 30 in. Mean Sea Level ag o£ 0 — 10 — 15 — 20 — 25 — 3(1 — O £ 0)ao CD <fc-=0?, ''/*"\ /{'^S. ?&<£. 'T— T". -5"" '^ * *,",""*, * •.' •. * ** " \ • ** • *'. J" ' ' * i • V • *- •* * * '. ' •* : .' f 13^- •l- <E O 01 CO T r1i i 2 f 1 (0°§£ 7 » 1 1 3) •- C4-01 Oa a.-j^ a 119.7 117.0 ^ at £5£_ ^S =*- oa V1S8 14.1 * (ft '^ 0<^ ^™ • co^ ML-SM SM SM/ML GEOTECHNICAL DESCRIPTION Logged Bv KAB Sampled Bv KAB ARTIFICIAL FILL @ 0': Olive-brown, moist, massive, olive-gray-green, to brown mottled, damp (clasts) to silty fine to medium SAND, abundant randomly oriented TERTIARY DELMAR FORMATION CTd) @ 3': Light gray to olive-gray, damp, massive, dense, silty fine to medium SAND to SANDSTONE @ 5': Olive-green, damp, very dense, silty, fine to coarse micaceous SAND to moderately indurated SANDSTONE. Driller reports difficult drilling due to well-cemented material sandstone is massive with abundant iron-staining water flowing on top of well-cemented material " @ 10': Light gray, slightly damp, very dense, silty fine to medium SANDSTONE, with 5-10cm clasts of olive-green SILTSTONE ~\ (spheral) f Total Depth = 11 Feet Practical Refusal at 1 1 Feet Perched Ground Water at 5 Feet Backfilled: 7/13/98 - - - - 505A(11/77)LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG LB-2 7-13-98Date Project Drilling Co. Hole Diameter Elevation Top of Hole CALSO Ltd. San Diego Drilling Sheet 1 of 1 Project No. 980161-001 Type of Rig Bucket 12 in. 151 ft. Drive Weight Ref. or Datum 0-30% 5.000 Ibs.; 30-60'. 389 Ibs.; 60-90% 2.446 Ibs. Drop 30 in. Mean Sea Level •C:2 a»&*<=>Z o — 5 — 10 — 15 — 20 — - 25 — 30 U»_ £ 0>Q.O«_i U) 7777~77 ?VV* TrTTyf J.V||1 — *,i.5r <i§L ' •*-'!g*U '^f ^r.^7 . * '• '**' "'. ' •• .- ' '' •• V > * * ••' '*"' • ^ • '' •' .* '*' '*'• \ ^ - ' V.'.' -;.'v "$:^7.* " • r*»* • ; /.. V ;i "^rnijj ."^Ti^of s^ .' .' • '. '. "• @? U)0)"O3+- •»- ^ O 0) (L m(0 Bag-1 @0'-2' . ^- IA O 3 ° Q. HU2 •push-6"m in 3 Upush 4" IT 2 HUnPn 4 Ipush-e" • 1n •f- yi ^N <u u°<3 3»~ a 101.0 103.4 0,8 3 . ?? SgU 18.4 19.8 v 52_ o°. CO '5=CO ML ML/SM GEOTECHNICAL DESCRIPTION Logged Bv KAB Sampled BY KAB TERTIARY DELMAR FORMATION @ 0'-2': Olive-green, damp to moist, clayey fine sandy SILT, abundant roots, moderately porous @ 2': Gradual contact material becomes mottled green-gray and brown @ 3': Olive-green, damp, soft, SILT, with abundant gray-green clasts of silt and scattered marine shell fragments ~ @ 5': Olive-green, moist, soft, slightly clayey SILT, abundant nodules of dark "olive-green silt @ 7': Material becomes lighter in color to light olive-green, damp, fine sandy SILT, material remains friable and massive to indistinctly bedded . @ 10': As above sample tube damaged, sample disturbed, no recovery @ 12': Material becomes fine sandy SILTSTONE with a marked increase in cementation scattered randomly oriented iron-stained discontinuous fractures @ 15': Dark olive gray-green, damp to moist, slightly clayey SILTSTONE, - @ 19': Perched ground water at contact with light gray, damp, fine sandy SILT to silty fine SAND Total Depth = 21 Feet Perched Ground Water at 19 Feet Backfilled: 7/13/98 - . 505AC 11/77)LEIGHTON & ASSOCIATES 1 1 GEOTECHNICAL BORING LOG LB-3 Date 7-15-98 Project _ _ Drilling Co. _ Hole Diameter CALSO Ltd. San Diego Drilling Sheet 1 of 1 Project No. 980161-001 Type of Rig Bucket 30 in.Drive Weight Elevation Top of Hole 157 ft. Ref. or Datum 0-30'. 5.000 Ibs.; 30-60'. 389 Ibs.; 60-90'. 2.446 Ibs. Drop 30 in. Mean Sea Level •4™ illIJ o — 5 — 10 — 15 20 — — - - in — u .C 0) 2°CD . . . , i i^V.. $4 y/ V* * *._ f"*"^' SI if '^~^-x- J^- "*r*^. "\pv^J ^< VM tf^!^: ' f • ,'\'^ \X •'• {' {.f: | , ^\ f'l ' ' ' • J. ' 1 , ' U)01•D •t- -»- F:N60E 25E S:N80E ION C:N30E 4N O rtlW rteMtoCO l 2 3 4 5 +• 3 ° £ <n £j jush 6" 2 3 5 8 15 +- c£01 UQ Q. 3,^ Q 107.7 106.3 111.7 119.2 124.9 C_^ = 4- •8^cc8 18.8 19.4 17f7 14.3 11.8 »to ^^ j? •0 . *""" "*} cS3 ML CL ML GEOTECHNICAL DESCRIPTION Logged Bv JD/MRS Sampled By JD QUATERNARY LANDSLIDE DEBRIS @ 0': Olive-green, moist, firm, sandy SILT with highly fractured and mixed texture, minor roots and organic matter - @ 4': Grades to olive-green, moist, stiff, sandy SILTSTONE, fractured into coarse blocks, fractures randomly oriented, diffuse contact with above, massive texture within blocks, minor cemented zones are randomly disturbed hi unit, discontinuous @ 8.5': Diffuse contact with olive-green, moist, stiff, silty CLAY, with slickenside texture, many fractures and slip surfaces. Iron-oxide and manganese oxide staining along slickensides, minor roots @ 11': Grades to light olive-green, moist, stiff, sandy CLAY, fractured with iron-oxide stains along fractures, slickensides larger but less frequent ® 13': Slickensides layer, continuous around boring @ 14': Olive-green, moist, hard silty CLAYSTONE ® 15': Rupture surface: highly sheared zone, 2 to 3 inches thick, gray-green very moist, soft, silty CLAY <9> 16': As above, abundant fractures and slickensides continuous around boring TERTIARY DELMAR FORMATION @ 17': Dark green, moist, hard, sandy SILTSTONE; fractured andsomewhat concreted, massive, much denser than above, fractured clay-lined @ 20': As above, hard - @ 22': Sharp contact with dark gray/olive-green, moist, hard, unoxidized sandy SILTSTONE, massive, unfractured, competent @ 25': As above, hard - \Refusal to continued drilling L Total Depth = 27 Feet No Ground Water Encountered at Tune of Drilling Backfilled: 7/15/98 505AC11/77)LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG LB-4 7-14-98Date , Project Drilling Co. _ Hole Diameter Elevation Top of Hole CALSO Ltd. San Diego Drilling Sheet 1 of 2 Project No. 980161-001 Type of Rig Bucket 36 in.Drive Weight 0-30'. 5.000 IPS.; 30-60'. 389 Ibs.; 60-90'. 2.446 Ibs. Drop 30 in. ft. Ref. or Datum Mean Sea Level ^ ag ai o — 5 — 10 — 15 — 20 - — 25- 1 30 O !E 0)&3& *. % ' '';..'; <"V -=^s, -_r-_- -£f-£-_ — "^ T— -• — IT - ^/TV— ' If** .. "* • 1.' •.-"•<' _!'• -_. __' • -^^l • — ~^J ^5? * ' N.'•TT^H- /f. ' ^ ' ' •- ' JwllliJT^T~ ) /•/' 4"!^'^i — U)01TJ 4- +- C:N30W20E C:N60W 8N F:N65W 20N J 01 iw 4- "•^ f a. 1 I pushn 2 1 pushn 3 | 1 NnHN 4 ipush 6"• 2-6"nHNHH 5 I 1 [ L 3) 01 Uan. 3) a 103.6 105.7 101.4 132.9 Sf•^"c o-£ o 20.7 19.1 21.9 16.9 g * _tA ^^ MB * C/J O C^CO SM/CL CL CL SM/CL CL CL GEOTECHNICAL DESCRIPTION Logged Bv JD/MRS Sampled By JD OUATERNARY^LANDSLIDE DEPOSITS @ 0': Orange-brown, moist, medium dense, silty fine to medium SAND with thin lenses of olive-green, moist, firm, sandy CLAY, with zone dark brown clayey sand, abundant roots and organic fragments - @ 6': Olive-green, moist, firm, CLAY with slickenside texture, some manganese oxide staining and calcium carbonate nodules @ 10': Irregular contact with olive-green, massive moist, firm, silty CLAYSTONE, highly fractures, disturbed and slickensided texture to fragment faces, randomly oriented with manganese oxide, calcium carbonate, and iron-oxide stains in fractures and slickensides, occasional roots - @ IT: Irregular indulatory contact with grayish green, moist, very dense, silty SANDSTONE, well indurated and cemented @ 18': Grading to silty CLAYSTONE @ 19': Landslide failure zone: Olive-green, moist, firm to soft, silty CLAY/CLAYSTONE with large very slickenside texture between fragments which are massive inside, some oriented - DELMAR FORMATION @ 22': Olive grayish green, moist, dense, silty CLAYSTONE with randomly oriented fractures, continuing iron-oxide stains and caliche • - @ 26': As above with some randomly oriented fractures and slickensides @ 27.5': Water seep encountered @ 29': Fracture, polished/slickensided continuous around boring 505A(11/77)LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG LB-4 1 Date Project Hole 7-14-98 rt ng Co. rinn Top of Hole CALSO Ltd. San Diego Drilling Drive Weight 0-30' ,5,000 Ibs. : ft. Ref. or Datum Sheet 2 of 2 Project No. 980161-001 Type of Rig Bucket 30-60', 389 Ibs.; 60-90', 2,446 Ibs. Drop 30 in. Mean Sea Level £i a~ 30 — 35 — 40 — 45 — 50 — 55 — fft — O 48m_i '& -f-i 2?n ^~* """""' * •.-TV'. 01TJ <E C horizontal 1 C/) 2! a. 6^6J ' • i» 1- fl 3t•V U>/-scs-<u u00. o ^% fi">§ °cE3 19.7 __ * * CO CL CL/SM GEOTECHNICAL DESCRIPTION Logged By JD/MRS Sampled By JD DELMARB3RMATION @ 30': Olive-green, damp, very dense, silty CLAYSTONE, randomlyfractured with fracture surface polished and striated iron-oxide stains on fracture seepage on fractures, some fractures continuous around boring @ 36': Grades to light olive-green and tan interbedded with gray, moist, hard/dense silty CLAY and silty SANDSTONE, randomly fractured - " Total Depth = 41 Feet Ground Water Encountered at 27.5 Feet Boring Backfilled with Soil Cuttings on July 16, 1998 - - - - 505A(11/77)LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG LB-5 Date 7-16-98 Project Drilling Co. Hole Diameter Elevation Top of Hole CALSO Ltd. San Diego Drilling Sheet 1 of 2 Project No. 980161-001 Type of Rig Bucket 30 in.Drive Weight 0-30'. 5,000 Ibs.; 30-60'. 389 Ibs.; 60-90'. 2.446 Ibs. Drop 30 in. ft. Ref. or Datum Mean Sea Level »!<§£ o — 5 — 10 — 15 — « 20 — - - 25 — 10 o\lL.CD ^ ^- . f , . -^ -u^C g$£y^yL ~\j-7~ -*——,_ .CTV^ ^~^-f~ X^X xJ-'^ 'r*-. -"•• •""^.T- ;^?5r *-*-- '*S' • /*_• -s_- .'-~- x^l ?£J ^C^ ^ ' '£-—*/'"-— x§ _T._£L .'" — 1% J^^~/~*j » T»— ." *^ -~V-i_ in01TJ 4- <E C/S:N60E 40S F:N30E 37S 0 <u fflCO 4- — " fflQflJ 0. 1 • push r1 2 I push Bag-2 I 2io'-irr1 3 rn • •i ' • -H 01 O Q ^r 105.1 106.0 105.9 108.0 g.8 ^Qj 1^*- oo 18.6 19.9 19.3 2 ITrl 82 0^ ^ • O5 CL CL ML SM/ML ML CL ML GEOTECHNICAL DESCRIPTION Logged By JD/RKW Sampled By JD ARTIFICIAL FILL @ 0': Red-brown, brown and olive-green, moist, soft, mixed, sandy CLAY,with roots and organic material - TERTIARY DELMAR FORMATION@ 4.5': Olive-green, moist, soft, sandy CLAY, highly fractured andslickensided texture, iron-oxide and maganesium oxide stains alongfractures, randomly oriented with localized cemented zones @ 8.5': Becomes less fractured and blocky @ 9': Diffuse contact to dark olive-green, moist, firm, clayey SILTSTONE, randomly fractured and slickensided, massive within blocks with iron-oxide stains @ 12': Diffuse contact to dark olive-green, moist, firm, silty fineSANDSTONE/fine sandy SILTSTONE, with less frequent but more continuous fractures and slickensides @ 14': Diffuse contact to olive-gray, moist, hard, clayey SILTSTONE with few fractures @ 16': Discontinuous and irregular contact with olive-green, moist, stiff.clayey SILTSTONE, with randomly oriented fracture sand slickensides @ 18': Diffuse contact to massive, olive-gray, moist, very hard sandySILTSTONE @ 20': Minor seepage along fractures @ 21.4': Grades to dark olive-gray, moist-wet, firm, clayey SILTSTONE withrandomly oriented fractures and slickensides, iron-oxide stains onslickensides, with seepage along fractures . @26.6': Potential rupture surface: 1/16" thick plastic remolded, light brown, _ moist, soft, CLAY, slickensides on surface @ 26.7': Light gray, moist, soft, clayey SILTSTONE, with abundant fractures _ and slickensides, randomly oriented @ 28.5': Olive-gray, moist, very hard, sandy SILTSTONE, with randomly oriented fractures and slickensides 505A<11/77)LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG LB-5 Date . Project Drilling Co. Holei 7-16-98 CALSO Ltd. San Diego Drilling Sheet 2 of 2 Project No. Type of Rig 980161-001 Bucket 30 in. Elevation Top of Hole ft. Drive Weight Ref. or Datum 0-30'. 5.000 Ibs.; 30-60', 389 Ibs.; 60-90', 2.446 Ibs. Drop 30 in. Mean Sea Level Depth(feet)30 — 35 — 40 — 45 — 50 — 55 — o !croQ.Oid _i & ^^ >£ s^ ••&:' in<uTJ 4~ <E 0 Q) mU) +- ,n O 3° Q. 3)4- SH-U °£ h ,^N ju-Mo i stuContent• (11 , _ 05 "530) ML GEOTECHNICAL DESCRIPTION Logged BY JD/RKW Sampled By JD TERTIARY DELMAR FORMATION (Continuedl @ 30': Olive-gray, moist, very dense, clayey SILTSTONE, with randomly oriented fractures and shckensides @ 33': Diffuse contact to dark olive-gray, moist, very hard, massive, sandy SILTSTONE » ^Refusal to continued drilling / Total Depth = 38 Feet Ground Water Encountered at 20 Feet Boring Backfilled with Soil Cuttings on July 16, 1998 - - 505A(11/77)LEIGHTON & ASSOCIATES i 1 GEOTECHNICAL BORING LOG LB-6 Date 7-17-98 Project Drilling Co. Hole Diameter Elevation Top of Hole CALSOLtd. San Diego Drilling Sheet 1 of 1 Project No. 980161-001 Type of Rig Bucket Drive Weight ft. Ref. or Datum 0-30'. 5.000 Ibs.; 30-60', 389 Ibs.; 60-90'. 2.446 Ibs. Drop 30 in. Mean Sea Level ^ <uj o — 5 — IfkIVJ 15 — 'ZO ; - 25 — - in — o 2 enao t5 .v .•-•• ,-. . "*-'/ ''• • ' ' j,.'.".; • . ' * l > « ^ •^— — • -=^^ ~7— •r\ / , / ^^x J\. -/——•—-J-^^ Zr^]L ^^-_~ /H^" ""o^ )^ '$> \5y%i\x V^ S^""^ 7^ ~~7^" -J '_ at•o3-t- *; <E C:N10W45W F:N50W 18NE O (U ni(A +- |£ Aa. 31 "iJL 11 .3,^ (h /^> -^Is O ^«^~ o 2 ^82 °S* O v"jto SM CL CL/CM CL GEOTECHNICAL DESCRIPTION Loeeed Bv JD/MRS Sampled By JD QUATERNARY LANDSLIDE DEBRIS @ 0': Tan, orange-tan and brown, moist, medium dense, silty fine SAND,colors mixed, with abundant roots and organic material . @ 4': Light olive-green, moist, firm, silty CLAY, small fragments, highly disturbed @ 9': Olive-green, moist, soft, silty CLAY, highly fractured and disturbed, seepage along fractures, some caving @ 10': Seepage along fractures @ 12.5': Rupture surface 1/2-3/4-inch thick, gray, soft, wet plastic CLAY, hole belled out +/- 6 to 12" for 18" above, continuous, slightly undulatory, minor roots, seepage perched on contact TERTIARY PELMAR FORMATION@ 13': Olive-gray, green, moist, stiff silty CLAYSTONE, moderately fractured, fracture slickensided with limonite staining, randomly oriented blocky appearance @ 16': As above, becomes very dense, some limonite stained fractures around boring, fewer polished surfaces @ 19': 6" thick zone of slightly less dense, more fractured than above @ 20': Olive-gray, damp to moist, very dense, silty CLAYSTONE, moderately/fractures randomly oriented with limonite stains and ' slickensides parting surfaces - Total Depth = 28 Feet Ground Water Encountered at 10 Feet Boring Backfilled with Soil Cuttings on July 17, 1998 505A(11/77)LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG LB-7 Date 7-17-98 Sheet Project Drilling Co. Hole Diameter 30 in. Elevation Too of Hole ft. CALSO Ltd. San Diego Drilling Drive Weight 0-30', Ref . or Datum Project No. 980161-001 Type of Rig Bucket 5,000 Ibs.; 30-60'. 389 Ibs.; 60-90', 2,446 Ibs. Drop 30 in. Mean Sea Level 11 o — 5 — 10 — 15 — 20 — - - 25 — - - - - 30 u iS(0-1 CO * .' ?. \'< \ ""» » '* - .;•"' :**'?*"w r »-c"" -17~^~/— N- ^% 2sJ/-* T — ^-_ ^|v *~~^~~ % ^ T^fT-^-•in ~T~~v-C~'/_____ • —7" ~~\ ^j> ^~. Z^Z! 57^'* • •*•"''• «* • •'- r'->. ." .• '. .V i '•}';' • «' '^.••"^ '» "•'•!; ---"'*• __?.-_ •i? -H -t- •*- C:N80W 32W RS:N25E 4W 6 (U 1CO •^ it °" 3>+• C?0) U°5 Ul Q ^oj-5 5s E oo 2 *m ^^tfl .» M« * y) O s"vCO SM CL CL ML SM GEOTECHNICAL DESCRIPTION Logged Bv ID/MRS Sampled Bv JD QUATERNARY LANDSLIDE DEBRIS @ 0': Tan, orange-tan and brown, moist, medium dense, silty /clayey SAND with abundant roots and organic fragments @ 3 '-5': Olive-gray green, moist, stiff, silty CLAY with roots and some organic fragments, highly fractured and mixed texture - @ 6': Olive-green, moist, stiff-hard, silty CLAY, within roots, fractured texture-medium, with slickensides along fractures, with iron-oxide and manganese oxide stains @ 11': Dark olive-green, moist, wet, silty CLAY, medium fractured texture, with highly slickensided texture, some roots, seepage along fractures, iron-oxide and manganese oxide staining and fractures @ 14': As above, wet 1 @ 15.5': Rupture surface: light gray, wet, soft, CLAY, sharp contact above * and below DELMAR FORMATION @ 15.6': Dark olive-green, moist, silty CLAY, moderately fractured texture. highly slickensided, large slickensides fairly continuous @ 20': Gray, moist, very hard, clayey SILTSTONE, massive with minor fractures with iron-oxide and manganese-oxide stains within them @ 23': Tan and orange-tan, moist, very dense, silty fine SANDSTONE, iron-oxide stains, some hydrogen sulfide accumulations massive @ 24.5': Orange and red-brown, moist, very dense, silty fine to medium SANDSTONE with fine interbeds of brown and gray sandstone, gypsum undulations @ 28': Tan, moist, very dense, silty fine SANDSTONE, iron-oxide stained with some manganese accumulations, massive 505ACI1/77)LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG LB-7 Date 7-17-98 Project Drilling Co. Hole Diameter Elevation Top of Hole CALSO Ltd. San Diego Drilling Sheet 2 of 2 Project No. Type of Rig 980161-001 Bucket 30 in. ft. Drive Weight Ref. or Datum 0-30', 5.000 Ibs.; 30-60', 389 Ibs.; 60-90'. 2.446 Ibs. Drop 30 in. Mean Sea Level TT Q) n! OJ ^ 30 — 35 — Af\ 45 — 50 — 55 — 60 — U £. 0)Q.Om_i & -•.'•••*'/ *^* .", V:> ••' Is*'-"i-.v •** ** "* . '& i '.''•"' (A(U •1-•f-<E * 9 01 1 4- IA °2 oo11- o. 5 C«4-Q) Ik CD ^L a .8 Is *1u fa o« '53w SM GEOTECHNICAL DESCRIPTION Logged By JD/MRS Sampled By JD TERTIARY DELMAR FORMATION fContinuedl @ 30': Tan, moist, very dense, silty fine SANDSTONE, iron-oxide stained and some manganese oxide accumulations, massive """ - - @ 35': Orange and red-brown, moist, very dense, silty fine to medium SANDSTONE ~ Total Depth = 40 Feet Ground Water Encountered at 1 1 Feet at Time of Drilling Boring Backfilled: 7/17/98 - ' - - 505A(11/77)LEIGHTON & ASSOCIATES 1 GEOTECHNICAL BORING LOG LB-8 7-17-98 SheetL»aie __ • -• - Pfnjprt Drilling Co. Hole PiamptPr 30 in. Elevation Top of Hole ft. CALSO Ltd.Project No. 980161-001 San Diego Drilling Type of Rig Bucket Drive Weight Ref. or Datum 0-30'. 5,000 Ibs.; 30-60'. 389 Ibs.: 60-90', 2,446 Ibs. Drop 30 in. Mean Sea Level £2n <" &«o-J5 0 — 5 — 10 — 15 — 20 — 25 — U Q.O CD '• • '-llxi* ••SSi V- •-~l '< 7~y- !• :'-r." •'<r- •• !"*./—"'.^"'"'77" ^.-h-!'.' !!?-£ — ^=- — ~ •?~~5~''* — j^~ §-. £& v^H ??l i ** * • i * * *• * ' *» * ^'%^i*"' V)(U•o ' 4- <E O 0114(/) +-,. oSo' 1 1o11- "~* / Q. 5 cC01 U °SQ/ 3»W 0 a.3 5t-MoislConten2 «5J5 • o3w SM/CL CL/SM CL SM/ML SM ML GEOTECHNICAL DESCRIPTION Logged Bv JD/MRS Sampled By JD QUATERNARY LANDSLIDE DEBRIS @ 0': Light brown and orange moist, medium dense, silty fine SAND, mixed @ 1-1.5' light olive-green, moist, stiff silty CLAY, highly fractured/mixed texture, roots • @3.5': Olive-green, moist, stiff hard, silty CLAY, moderately fractured, slickensided texture, coarsely mixed with white silty fine to medium SAND, roots " @ 6': Olive-green, moist, stiff, hard, silty CLAY, highly fractured with slickenside fragments @ 7.7': 1-1/2" thick gray, mixed, moist, soft, CLAY with 1/16" thick dark gray, soft, clay @7.8': Dark olive-green, moist, very dense SILTSTONE, fractured with few slickensides mostly massive, iron-oxide and magnesium oxide stains @ 10': As above, no fractures or slickensides massive @ 12': Gradual contact to light gray brown, damp, very dense, silty fine SAND, sandy SILTSTONE, with iron-oxide stains @ 14': Irregular erosional contact to light orange-brown, damp, very dense, silty SANDSTONE, fine to medium hematite staining on contact _ @ 19': Light gray, moist, very hard, sandy SILTSTONE - Total Depth = 23 Feet Ground Water Encountered at 20 Feet Below Ground Surface at Time of Drilling Boring Backfilled with Soil Cuttings on July 17, 1998 505A<11/77)LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG LB-9 Date Project 7-20-98 CALSO Ltd. 'il Drilling Co.San Diego Drilling Sheet 1 of Project No. Type of Rig _ 980161-001 Bucket Hole Diameter Elevation Top of Hole 30 in. ft. Drive Weight Ref. or Datum 0-30', 5,000 Ibs.; 30-60', 389 Ibs.; 60-90'. 2,446 Ibs. Drop 30 in. Mean Sea Level £mQ-m01,2at o — 5 — - 10 — 15- 20 — - - - U -C 0)0.0<0_J CD s*>> •>*• 'vQTvJ VN. *»-£ •\Vii'-1 / -i^ /-X- -V T^•. *"••'. " " * . •''•• -V *i '. /£??¥, *f£*$ * * -l' • SV'.**» ' \ *•'* *** * .1 *"•*" » •• » j" •'•'• :Vf *, " *'•• HS;•" ', •• * '»• • : O.'.'!~ "^".' iAv 'ITlr-'. '•'•^-/ Ns ~^-f- a>TJ ^—•— ^ «_ ~ C:N80E 4E O 01 Q, <sen - - - - _ - - - - - - " - 4- 3.~O~~* f tO Q) U« 4- cC 01 UL_J 0, 3)t.a \ o>8 4-"tw£._ o* °"ctf Q U 2 ~ !2 "*"CJCJ ^ (/)Z •O "^ww ML/SM ML/SM ML CL SM ML SM CL SM SM/CL CL GEOTECHNICAL DESCRIPTION Logged By JD Sampled By JD ARTIFICIAL FILL @ 0': Olive-green and tan, moist, medium dense, sandy SILT and silty SAND, mixed TERTIARY DELMAR FORMATION @ 2': Olive greenish green, moist, hard, sandy SILT with fine interbeds at light gray, moist, dense silty SAND @ 3': Olive-gray, moist, hard, clayey SILTSTONE, with iron staining, gypsum accumulations @ 4': Dark brown, moist, stiff, CLAY, fractured and slickensided @ 5': Yellow and tan, moist, dense, clayey fine medium SAND, orange stained at base @ 6': Greenish gray, moist, hard, clayey SILTSTONE, minor fracturing, with iron staining throughout @7.5': Orange-tan, moist, very dense, silty SANDSTONE widi some concretions @ 8.5': Gray-tan, moist, very dense, silty SANDSTONE @ 10': Tan, orange, moist, very dense, silty SANDSTONE, massive, minor dark interbeds <5mm, well indurated @ 15': Light gray/olive, moist, hard, CLAYSTONE, mixed into sand @ 16': Tan-white, moist, very dense, silty medium SANDSTONE, massive @ 19': Mixed, finely interbedded, red-gray silty SAND and CLAY @ 19.8': 1" thick, gray, moist, soft, CLAY, remolded @ 20': Dark gray, moist, hard, silty CLAYSTONE, coarsely fractured with iron-oxide stains, massive - Total Depth = 25 Feet ' Ground Water Encountered at 19 Feet at Time of Drilling Boring Backfilled with Soil Cuttings on July 20, 1998 505AC11/77)LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG LB-10 Date Project Drilling Co. _ Hole Diameter Elevation Top of Hole 7-20-98 C ALSO Ltd. San Diego Drilling Sheet 1 of 2 Project No. 980161-001 Type of Rig Bucket 30 in.Drive Weight 0-30', 5.000 Ibs.; 30-60'. 389 Ibs.; 60-90'. 2,446 Ibs. Drop 30 in. ft. Ref. or Datum Mean Sea Level £-»-&! 0 — 5 — - 10 — 15 — ' 20 — - - 25 — — — 10 u r~ rn^^ wQ.O CD •^..^-- ',' *~ ^7 • ^~>~T •Y-. ."^ . *A '•'*,"•'.» . V " t. w '•' • • ~ ^>£>v-X,^* / — y^"~ ^Z^1^yi>, T^X ^&i ^\4^\ ^ \~• *"^'i ;*-£ l_j . X „ , - *f .*• ^"^ * ^LT^' o«-'C T33 •f- 5:^ S:N70W 4E S:N75W 16E S:N85W 2SE C:N10W 15W 6 01 1(0<n •»- §.»_ a! •»- c? °5ji a , t* 5+- 5| o |2° . * 05 CL SM CL SM ML GEOTECHNICAL DESCRIPTION Logged By JD/MRS Sampled By JD QUATERNARY LANDSLIDE DEBRIS @0': Gray and olive-green, moist, firm to soft, sandy CLAY TERTIARY DELMAR FORMATION @ 4.5': Tan, white and orange-tan, silty fine to medium SANDSTONE, with orange iron-oxide stains throughout, grass along contact @ 9.8, 10.2, and 10.8: Three clay seams interbedded in DelMar Formation: Gray and light brown moist, soft, CLAY, remolded and slickensided, 1 " thick @ 12.7: Irregular erosional contact, generally horizontal with olive-green, moist, soft, clayey SILTSTONE highly fractured and slickensided, randomly oriented @ 13.2': Becomes less fractured and slightly more firm, olive grayish green, ~~ moist, hard clayey SILTSTONE, iron-oxide stains with fractures, blocky appearance @ 16': Diffuse horizontal contact with gray, moist, very hard, sandy SILTSTONE @ 18': Semi-continuous fracture around boring - @ 21': Irregular contact with, dark gray, moist, very hard, sandy SILTSTONE, well indurated, massive @25': Becomes coarser 505A(11/77)LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG LB-10 Date 7-20-98 Project Drilling Co. Hole Diameter 30 in. Elevation Top of Hole ft. CALSO Ltd. San Diego Drilling Drive Weight 0-30', Ref. or Datum Sheet 2 of 2 Project No. 980161-001 Type of Rig Bucket 5,000 Ibs.; 30-60', 389 Ibs.; 60-90', 2,446 Ibs. Drop 30 in. Mean Sea Level il 30 — 35 — 40 — 45 — 50 — 55 — is*_. CD 01TJ •t- •t- <E 01 Q. 10CO §8 S. CH-OI UD«f/ a Mo i stureContent <X> |*[fl ^^ r • ^ GEOTECHNICAL DESCRIPTION Logged BY JD/MRS Sampled BY 3D Total Depth = 30 Feet No Ground Water Encountered at Time of Drilling Boring Backfilled with Soil Cuttings on July 20, 1998 - - - - - j 505AO1/77)LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG LB-11 Date Project 7-20-98 ct jng Co Diameter 30 in. itinnTopofHole ft. CALSO Ltd. San Diego Drilling Drive Weight 0-30', Ref . or Datum Sheet 1 of 2 Project No. 980161-001 Type of Rig Bucket 5,000 Ibs.; 30-60', 389 Ibs.; 60-90', 2446 Ibs. Drop 30 in. Mean Sea Level f?m <U Q^ o — 5 — — 10 — ~ t ~ 15 — — _ 20 — - 25 — — — in — u "£ o(0—1 o •u ,-....- •,;' '..; ':: ',"'• i -:"'*-j<i• ';'' '*'. — «- ' 7-^- ' — - , . f~ry^~--. ^J^J^t^s^ » *1 '..'"S-1 -- *oo#" •^/t- "^ — *• 1•'Vc-l-... '^7^-j, >-cT T£ ^' •n^.V-?1* Hl2*i **^ "^ * ^ " * * " } « ' » "'"•* '* •* '* " , X* * t *,' ^ ** ' ."-'•j-V .» . *- ,\ . . • \ * f'll^f '&&-'zS?*"": ^'C3i^'./^r^- '$£ to0)TJ ._ 4- S:N30W 24N O (U ^ U) 4- gu. — , <O (u 4- cs-IU Uo a ^£.a a.8 |c"* QJ °£E Ou • trt ^^ "^Z • U)^ SM/SC CL CL ML ML/SM SM K/HirlLj CL GEOTECHNICAL DESCRIPTION Loeeed B\ JD/MRS Sampled E\ JD ARTIFICIAL FILL @ 0': Light brown, tan, olive-green and red-brown, mixed, moist, medium dense, silly/clayey SAND, with roots and organic matter • QUATERNARY LANDSLIDE DEBRIS @2.5': Light olive greenish gray and reddish brown, moist, soft, silty CLAY with formadonal fragments mixed in roots and organic material, highly disturbed @ 2.5': Dark olive-green, moist, firm, CLAYSTONE, fractured and slickensided, with roots, massive within fragments @ 5': Olive-green, moist, firm to hard, elayey SILTSTONE with abundant fractures and slickensides, with iron-oxide stains along fractures @ 10': Scarp exists boring on north side TERTIARY DELMAR FORMATION @ 12': Diffuse contact to dark olive-green and red-brown, moist, hard, very dense, sandy SILTSTONE and silty SANDSTONE interbedded (6"-12"), with boring iron staining in sandstone and along fractures in siltstone ~ - @ 16.2': Dark brown and red-brown, moist, very dense, silty SANDSTONE @ 16.7': Light gray/white, moist, very dense, silty SANDSTONE, well-cemented and indurated minor fractures with iron-oxide and maganesium oxide staining @ 17.8': Light gray, moist, very dense, silty fine to medium SANDSTONE, massive, grades to coarser at base with more iron staining, red-brown with some concretionary zones - - @ 25.5': Red-brown, moist, hard, sandy SILTSTONE, massive @ 26': Dark gray, moist, hard, clayey, SILTSTONE, massive @ 27': Light green and blue gray, moist, soft to firm, CLAYSTONE, highly fractured and slickensided, with minor iron- and maganesium-oxide stains „ 505A(11/77)LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG LB-11 i 7-20-98Date - Project Drilling Co. _ Hole Diameter Elevation Top of Hole CALSO Ltd. San Diego Drilling Sheet 2 of 2 Project No. Type of Rig 980161-001 Bucket 30 in. ft. Drive Weight Ref. or Datum 0-30'. 5.000 IDS.; 30-60% 389 IDS.; 60-90'. 2446 Ibs. Drop 30 in. Mean Sea Level r- I! 30 — 35 — 40 — 45 — 50 — 55 — O pCO '•• ~^_^ • •'o^; "T^T W:- • **' . •".v ;. *.' . -' »•' * * ' '** .' '";'" ''•'''.' • *7; .' ' '. * ', V. ' '; ' £ ]/ ' " * 1 3 4- o 01 1mCO - - - - - - . - - «8 Q. 3>•*- 0) O °3' 3> a /^?:^+-^§ °rEo0 . $aj ._ * O)^ ML SM CL GEOTECHNICAL DESCRIPTION Logged Bv ID/MRS Sampled By JD DELMAR FORMATION (Continued) @ 30': Grayish blue, moist, hard clayey SILTSTONE, minor fractures. mostly massive @ 34': Diffuse horizontal contact to tan/ red-brown, moist, very dense, silty fine SANDSTONE, massive, becomes reddish brown and coarser at base - - . _ @ 45': Dark gray, moist, very hard, silty CLAYSTONE, with some fractures, - mostly massive 1 \water Total Depth = 50 Feet Ground Water Encountered at 50 Feet Backfilled: 7/22/98 505AC11/77)LEIGHTON & ASSOCIATES I V 1 1 -* T 1 > 1 ii ^ 4- 1J , jT £8u ^ -3I ..IT) 00 ''I ' I -) U T3 1 1 Q ,4 1 > I- < 1 J ',5 DEPTH/FEET 11- 2- 3- 4~ 5- 6- 7- 8- 9- 10- 11- 12- 13- 14- 15- 16- 17- uites!1" a| © ®SOIL 1CLASSIFICATION ISYMBOL 11 523J2SJ 1 SUMMARY SHEET BORING NO. 1 ELEVATION 128.5 (*) LJght Brown and Light Gray Brown, Moist, Firm to Very Firm, Slightly Cemented Light Gray Contact Dips Down 23° to W., Light Gray, Very Moist, Soft, Thinly Laminated Gray and Light Brown,With Red Brown Color Bank/Marbled, Moist, Very Firm Slightly Cemented, With Scattered Claystone Chunks S35£y\\Not Cemented, Nearly Saturatec \Very Moist to Saturated, With || Scattered Coarse Sand Grains U Water Seeoaqe at 9.7' ilConlact Dios Down 15wto SSE.r^rrmiii ' *KSSSgllOlive Gray and Red Brown r £££&£||IScirurated to Very Moist, Very ^^3 Firm,Wfth Small Chunks of RS5SS9l|Clay$rone,Many Sllckensides © I 1 Moist f Merges lOlive Gray, Moist, Very Firm, 1 Slightly Cemented, Massive 1 Structures, No Bedding Planes, (Merges Blue Gray and Gray, Moist, Very Firm, Slightly Cemented 8 (*) PROJECT NO. 79-4- 12F SILTY FINE TO MEDIUM SAND SILTY CLAY SILTY FINE TO MEDIUM SAND DRIVE ENERGYFT. KIPS/FT.44.0 61.6 66.0 24.2 FINE SANDY CLAY II SILTY CLAY SILTY FINE SAND 99.0 FIELDMOISTURE% DRY WT.8. 9. 4 6 9.9 23.5 12.1 Continued on Drawing No. 3 Indicates Undisturbed Drive Sample Indicates Loose Bag Sample Elevations were obtained from Drawing Prepared by Brian BENTON ENGINEERING, INC.DRY DENSITYLBS7CU. FT.108.3 109.9 116.7 103.3 120.5 SHEARRESISTANCEKIPS/SO. FT.0.76 0.94 3.14 1.84 3.81 Smith Engineers, DRAWING NO. 2 *•— f _c jj S. 8<J uar- •*< t _i ^ > 1 ' £ IL O 1 / 18- 19- 20- 21- 22- 23- 24- 25- 26- 27- 28- 29- (r - - - ™ - ujee » iQ \i Q i ^SOILCLASSIFICSYMBCH 1 "m $/& *%&. SUMMARY SHEET BORING NO. 1 (Cont. ) Olive Gray, Moist, Very Firm, With Scattered Highly Cemented Lenses to 19. 1' Merges Light Gray to Gray, Moist, Very Firm, Slightly Cemented ,With Slight Clay Binder .Gray and Light Gray Brown, Moist, Very Firm, With Thin Lenses of Cemented Silry Fine Sand, Contact Surface Level Ltg FIrr So Sil it Gray Brown, Moist, Very n, Slightly Cemented, With ottered Lenses of Sandy tstone, Merges Olive Gray, Moist, Very Firm PROJECT NO. 79-4- 12F FINE SANDY CLAYSTONE SILTY FINE TO MEDIUM SAND FINE SANDY SILTSTONE SILTY FINE TO MEDIUM SAND FINE SANDY SILTSTONE |t Ul* 88.0 66.0 88.0 IK 14.5 6. 11 BENTON ENGINEERING, INC. 2 .9 |fc P 118.0 102.2 108.1 «ifc' < +7.45 3.07 3.10 DRAWING NO. 3 I J 1 I I I i i i i i i i ito U Q V) 00 6 I 2 I 1 J J Ul 3 DEPTH/FEET 11i1 — 2- — 7 8- o7 — 10- 11 12 13- 14- 15- 16- 17- 18- 19- 20- -SAMPLE 1NUMBER JSOIL 1CLASSIFICATION!SYMBOL 1• f SUMMARY SHEET BORING NO. 2 ELEVATION 148.0' feSSSSSlVerv Moist, Soft, Reworked and fTr ^\^^^3 Rede posited Claystone, Highly (jj ESSS53 Weathered and hractured L^^^^^^^^^J ^^^^^^3UJxTrSSj R^555>3 rWxJJJjCSSSSac\\ S\jJ KN.XXJJ ^Qt'urcl^e^fe^rrn rxxxxTjj » - © " (Gray and Ol i ve Gray . Very Moist | to Saturated, Less Disturbed, 1 Mixed with Slry Claystone, • i .| Medium Firm to Firm '{Highly Fractured, SI ickensfded |Medium Firm to Firm1 =-^:'.••'•••::'•'••'. ^^22223 Jx^^T^ESJTrv?]c^2SS3 5Jjvvv>J Co 'Lig ML_ n tact Dips Down 15° to NNW ht Gray Brown , Saturated , edium Firm , Highly Cemented Light Gray Brown, Saturated Medium Firm, Hole Caved in Between 7' and 14' Contact Dips Down 12wto NNW G ray and Ol i ve Gray , Satura ted to Very Moist, Medium Firm, highly Fractured and SMckensidec with Free Water in Fractures. Firm to Very Firm Con tact Dips Down 5W SSE , Light Brown and Gray Brown, \Moist, Very Firm, Slightly ICemented to Cemented, Inter- bedded with Thin Lenses of jSiltstone Light Brown and Light Yellow Brown Highly Cemented Lens SILTY CLAY CLAYSTONE \ SANDSTONE , / CM TVOIL 1 I FINE TO MEDIUM SAND SILTY CLAYSTONE SILTY FINE TO MEDIUM SAND DRIVE ENERGYFT. KIPS/FT.1.4 1.4 1.4 2.7 10.8 32.4 1 ?] 22 5 .6 24.5 22.2 16.8 12.0 DRY DENSITYLBSVCU. FT.103.6 103.1 99.5 101.4 108.7 119.0 B* 0.74 1.00 1.36 2.29 4.47- +7.45 Not Cemented Continued on Drawing No. 5 PROJECT NO. 79-4- 12F BENTON ENGINEERING, INC. DRAWING NO. 4 I• 1 £UlIt Ulo 20 r\ \21 — 22- 23- 25- - 26- 27- 28- 29- _ 30- 01 _o 1 — 32- 33 34- 35- 36- 37- 38- w 39- -dft- 32 "z 0 -^(§J S-fi u >§§§§ i^^^ *^^X^ B Hi ft ^^ ^^ ^^111iit^xS^xJ ^^ SUMMARY SHEET BORINQ NO. 2 (Cont. ) Light Brown to Light Yellow Brown, Moist, Very Firm, Slightly Cemented to Cemented, Highly Cemented Scattered Lenses With Scattered Small Chunks . of Claystone Light Gray and Yellow Brown, (Mottled) Very Moist to Saturated, Very Firm. Contact Surface Level • Gray and Olive Gray, Very Moist to Moist, Very Firm, Massive Structure ,With Few Fractures Merges (9) (10) • ^555IIPw&$$W? ^^^S; S«i^ Gray and Olive Gray, Moist, Very Firm, Massive Structure with Few Fractures Light Gray, Moist, Very Firm SILTY FINE TO MEDIUM SAND SILTY CLAYSTONE FINE SANDY SILTSTONE SILTY FINE TO MEDIUM SAND > £2 I* 29.7 20.8 48.0 44.8 FIEtOHSTUREDRYWTIX 13.4 15.1 12.4 10.9 fc . 1 & 115.3 107.9 121.8 121.4 Ul -* Is 6.21 4.85 6.90 6.19 PROJECT NO. 79-4- 12F BENTON ENGINEERING, INC. DRAWING NO. 5 vu 2at S? . S UlILia u_ 1_ 2- 3 4- 5_ 6- 7- 8_ 9- 10-1 w if 12! 13-1 v 14_ _ 15~1 +J 16- 17- 18I 19- 20- - ma s!g a| Qj®AILFICATIONMBOL0^&S xNxw xS§evjj ill SUMMARY SHEEToBORING NO. ELEVATION 178.0* Gray Brown and Brown (Mottled) Dry, Loose, Mixed with Clayey Fine to Medium Sand Moist to Very Moist £§o§i §§*!§! Contact Dips Down 60" to N.miis Vw5$5 *.X X X X N Olive Gray and Gray, Very Moist to Saturated, Soft, with Reworked and Redeposited Weathered Claystone [3 1 tSSSSSii C3 } t$$$$$t[22231i^^^^^^^^^^^ RxJJ^VXlI255S3 1 Con tact Dips Down 25 to N.r Gray and Olive Gray, Very 1 1 Moist to Saturated, Soft, Highly I Fractured and Slickensided, [Vertical Fractures, Partially Open ' jlwith Free Water In Fractures, I" " II Mixed with Silty Claystone ^ 1 i ©F Frof-tur*>« i i— — |« [Highly Fractured and Slickensided [^ | Few Open Fractures, with Free L___J Water in Fractures L^^^^^^^^l iP= Contact Dips Down 12° to W 1-1/2 "Thick Gray, Saturated, Soft Clayseam, Highly Fractured, Slickensided PROJECT NO. 79-4-1 2F SILTY FINE SAND £*t 1 Y*\./ /^ 1 A \/SILTY CLAY CLAYSTONE ENERGYCIPS/FT.in — itf 2.2 1.1 1.1 22.0 37.4 46.2 Ulfeo§£&ik 9° f* 14.1 17.3 27.4 22.2 18.1 20.3 Continued in Drawing No. 7 BENTON ENGINEERING, INC.DENSITY/CU. FT.>8SS 100.0 98.6 93.2 101.6 109.0 102.0 sljj aeS 0.83 0.73 0.65 2.17 - 4.64 3.76 • DRAWING NO. 6 1 ] Ul <PTH/FEETUlO f\f\£U 21 - 00 23 _ 24 25_ 26 _ r»"»27_ 28- 29- 30- - 31- 3?- 33- - 34- 35- 36 _ __ 37- _ 38- 39_ m^ 40- -SAMPLE 1IUMBER 1" «c SOILiSIFICATIONSYMBOL„., 2u SUMMARY SHEET BORING NO. 3 (Cont. ) 1 [ Olive Gray, Moist, Very Firm, j | Mixed with Silty Claystone, [ '.r' J Highly Fractured and. SI ickensided 'tf/ i^y^vv^ VvV Olive Gray, Moist, Very Firm, Massive Structure with Few Fractures Merges _ 1 | Olive Gray, Moist, Very Firm, 17)| 1 Highly Fractured and Slickensided l""*"] Free Water in Fracture,with I 1 Rust Stainsit • ® © ® § ^5§ ^^v*vx^OvxXXN ^§w ^^^s ^^^ ^slS ^^^ v^^i ^^g; ^^ ^owS? J^^^l^^^Xj =^^^^wv§li>^§^ • Olive Gray, Moist, Very Firm, Massive Structure,Wirh Few Fractures Brown and Light Gray, Moist, Very Firm, Slightly Cemented to Cemented, Scattered Thin Cemented Lenses, Merges Light Brown and Light Gray, Moist, Very Firm, Slightly Cemented with Scattered Highly Cemented Lenses Light Brown and Light Gray Yellow Brown and Brown (MotHed] Moist to Very Moist, VeryFirm, CLAYSTONE SILTSTONE CLAYSTONE SILTSTONE SILTY FINE SAND SILTY FINE TO MEDIUM SAND with Slight Clay Binder, Bedding Dips Down 10°to SSE Yellow Brown, Moist, Very Firm with Slight Clay Bnder, Cemented Bedding Dips Down 10°to SSE | PROJECT NO. 79-4-12F 1 /E ENERGY 1. KIPS/FT. 1M r~ 8™ 30.8 91.3 70.4 * 85.8 3UJZ li lye 19.8 11.6 10.4 12 Continued on Drawing No. 8 BENTON ENGINEERING, INC. .7 Y DENSITY 1BJCU. FT. IK.J0J 105.7 114.6 106.5 101.4 SHEAR ISISTANCE 1PS/SQ. FT. 1**J *5OCX 4.32 5.33 4.35 5.12 DRAWING NO. 7 1 Vi DEPTH/FEET 1— 41- — • 42- 43 — 44- 45 46- - 47- - 48- 49- 50- 51 -i 52 1_ 53- 54^ 55-, 56_ 57- 58- 59- woe-lUl SOILLASSI FICATIONSYMBOLU ^SSSx ^^^j§§§&? SUMMARY SHEET BORING NO. 3 (Copt. ) Yellow Brown and Gray Brown Moist, Very Firm, Cemented, \with Slight Clay Binder • k-wv%.-% k\^l VK-W«^»IU«| %.-v%JW«l BW r^^^^xi ^^v^u^^^5SSR^^^SSRJP^^^JP2^2S3 p^^^^^nRJ^BSjCS55«MN 6j) & (l$) (14) '^fy ^^s^/S ^s/ ^^s.% Y& ^^5^^^^OOvS^ '^^y^ ^^^ ^^^ ^P vwoo ^^w ^^^ ^ ^iil^*&fe tj/% $$/A i "•»IInw Rrr*vn . L*»vm Con fact Olive Gray and Gray, Moist to Very Moist, Very Firm Top 6" Badly Fractured and Slickensided With Large Amount of Seepage Massive Structure with No Fractures or SI ickensides, Merges Olive Gray and Gray, Moist to Very Moist, Very Firm Merges Gray, Moist, Very Firm,Cementec Merges Light Gray, Moist, Very Firm, Slightly Cemented to Cemented Light Gray, Moist, Very Firm PROJECT NO. 79-4- 12F SILTY FINE TO MEDIUM SAND SILTY CLAYSTONE SILTSTONE SILTY FINE SAND SILTY FINE TO MEDIUM SAND FINE SANDY SILTSTONE it!i 111.5 60.0 62.4 64.0 i z\;§i* 13.2 13.5 8.7 11. •4 BENTON ENGINEERING, INC. 8 DRY DENSITYLBS7CU. FT.105.C 120.9 106.5 115.4 1 4.44 7.08 5.72 6.58 DRAWING NO. 8 Ul Ulu. tUlO 0 1 - - 3- A 5- _ 6- 7/ — 8- 9_ 10- 1 1I 1 12- 13_ 14- 15- _ 16 17- 19- 20- ttice-IU1 sssi J-S^i P u SUMMARY SHEET BORING NO. 4 ELEVATION [!$f 0' fe^^y Medium Firm to Firm, Badly pSSSSSJFra (D L^ixx^c iaetured and Weathered ystone, Appears Reworked or ^"^ R^^^'j Re-deposited rvjjjvjv^j P^25^^3(Tj g££££j (2) E \ \ \ \ ^ Levfel Contact K^^^OIive Gray and Gray, Moist, ISSSSSVery Firm, Mixed with Siltstone, kSSS3Few Random Fractures, Massive BSS9 Structure ^^^^^^a I$S$SS3 RjJvJJj ^^^^^^355^^23K^SXN] ^^^^^^3Ct^CVxjRTrJTTTj [ [Contact Dips Down 15" to NNW (4j | jOlive Gray and Gray, Very Moist &Z& y$Y $/$ 1$S'Sytyj%m o Saturated, Very Firm, Badly Fractured, Appears Disturbed, Hi ickness Varies From 9 "to 12" Light Brown and Gray, Moist, Very Firm, Many Sllckensldes Fractures, Closed, Level Contact f«D [ |Light(jray brown and Gray ,Very ^-^ [.I [Moist to Saturated /Very Firm, [ | Bad 1 y Fro etured ,Many Large ^^^Slickensides, Soft Clay in Joints, ©IRo< Pa 3tlets,vVater Seepage at SSE rtion of Boring Level Contact Gray and Olive Gray, Moist, Very Firm, Massive Srrucrure,Few Random Fractures, Closed, Scattered Small Slickensides to 18' Depth , Scattered Lenses ,of Highly Cemented Silty Fine Sand PROJECT NO. 79-4- 12F SILTY CLAY SILTY CLAYSTONE CLAYSTONE FINE SANDY SILTSTONE CLAYSTONE SILTSTONE te ito 6.6 6.6 15.4 24.2 26.4 74.8 u IL UIU£ 9° 21.3 24.4 18.7 20.0 18.6 13.3 BENTON ENGINEERING, INC. |c go |!S 98.3 91.4 109.5 106.4 102.7 119.2 K 5 . ^t>85ll 0.76 1.20 2.75 2.53 3.05 4.91 DRAWING NO. 9 Ul > DEPTH/FEET-VT- 21- 22- 24- 251 26- — 21 ®SOIL 1CLASSIFICATION!SYMBOL 1'VJX/ 1 §§*&! SUMMARY SHEET BORING NO. 4 (Cont. ) Olive Gray and Gray/Moist, Very Firm SILTSTONE Gray Brown /Gray and Yellow Brown, Moist /Very Firm /Mixed With Silty Fine Sand (Cemented)7 FINE SANDY SILTSTONE light Gray /Slightly Moist /Very en TV Firm, Highly Cemented F[NE SAND Sandstone PROJECT NO. 79-4- 12F DRIVE ENERGYFT. KIPS/FT.156.2 105.6 FIELDMOISTURE% DRY WT.13.1 10.8 |c 120.5 121.0 SHEARRESISTANCEKIPS/SO. FT.+7.45 4.54 BENTON ENGINEERING, INC. DRAWING NO. 10 I 1 ' £Ulu. I UlO 0 — - 3 - 4- 5- 6- 7- 8- — 9- 10- 11- 12- 13- 14- 15- 161 17—I/ — 18- 19- 20- - Ul K-> Ul i| © LH o Qcluj> O ^§§ ^^^ ^^^ ^^^§||j|i ^^^5 ^^ ^1m ft SUMMARY SHEET BORING NO. 5 ELEVATION 170.0' Light Brown and Gray Brown, Dry to Slightly Moist,Loose, Scattered Rootlets, Porous with Small Chunks of Fine Sandy Siltstone Moist, Medium Firm to Firm, With Slight Clay Binder HSSS5| Olive Gray, Moist to Very Moist, BSSSjFirm to Very F?rm,Weathered Rfr"EH<3 Claystone, Appears Redeposited, rji Rj^^q Badly Fractured and Weathered ^^^^^?^^^^nP5J22S3 ^^^^^3K5^^53 P^^^^^^^^^^JJ25S23K^^^3|SS5^3^^^^^??jKSJ^JJJ ^^^^^jfl^^^^^3 _CSSSSaCoiitact Dips Down 40"to NNW ^^CT Olive Gray, Very Moist to Moist, ^^S Very Firm, Mixed with Claystone QL/ tSSSSl Highly Fractured, Random ESS3 Orientation of Fractures, ESSl Slickensided,Few Rust Colored K^^xJ Sta'ns I^M^j ^^^ © i^///// •••••••n Meraes Contact Dips Down 5 to NNW Olive Gray, Very Moist to Moist, Very Firm Merges Ol ive Gray , Saturated , Very Firm PROJECT NO. 79-4- 12F <UI TVOIL 1 T FINE SAND SILTY CLAY SILTY CLAYSTONE SILTSTONE CLAYSTON: > m actsi HI •• S u a 1.1 6.6 8 0 ,. o 15.4 • 22.0 39.6 UlHl|> §x 10.0 10.2 U c .. 5 20.6 21.0 t . gt 1§ 1S 74.3 88.6 1 AT £.101. 6 102.5 103.5 20. 3J1 09. 1 AC ^£ 5ll 0.47 1.27 n c i ,. 51 1.61 2.57 4.57 Continued on Drawing No. 12 1 DRAWING NO. BENTON ENGINEERING, INC. ,, Ul SUlu. I0 2tt— Ol/ 1 22- 23- 24- 25 26- 27l 28- 29- 30- 31- 32- 33- 34- 35- 36 _ 37- 38 39- 40-SAMPLE 1NUMBER |SOIL ICLASSIFICATION!SYMBOL 11 fc SUMMARY SHEET BORING NO. 5 (Cont.) Olive Gray,Saturated to Moist,Ver> :irm,Highly Fractured and Sllcken- BTJfrgjsidecl/lighlyUisturbedZone IV. 5' ESS§$S|fo20. 75 Zone Approximately J533335 Levol with Undulating Contact, 1... . .IV* '*"" us Stained Fractures, With j §52?23Svvvvl ^^^^^3 IW^MM •^^^^^i 222S2]3^^SS^^5555j2SSSS^555551^5JJ22 ^^^^^^^^J^SSSS555555 IS ^>r^ 1 ^ jfjt We of Po iter Below 20. 75'Zone Consists Discontinued Seams and Small ckets of Disturbed Material Olive Gray, Saturated to Very Moist, Very Firm Massive Structure Gray and Ol ive Gray/^oist, Very Firm ,Mixed with Clayey Slltstone, Massive Structure with Few Closed ^Fractures Ser 3/ W< an DC ies of Thin Clay Seams l/4"to 8",Soft,Sarurated,with Free iter in Seams Highly Fractured d Slickensided,ContactDips .wn 30° NNW No Clay Seams Gray and Light Olive Gray, Moist, Very Firm .Highly Fractured, RustStained Cjosea Fractures/ Thin Smears of Clay in Slickensided jFractures,Slickensides DipDov/n [30 to SW Light Gray Brawn, Water Seepage at 34. 8' Contact Dips Down 8uto NNE, Gray and Dark Ol ive Gray,Moist , Very Firm, Massive Structure Highly Cemented Merges Gra ,Ver M /and Dark Olive Gray,Moist, y Firm, Massive Structure erges CLAYSTONE SILTY CLAYSTONE SILTSTONE SILTY CLAYSTONE FINE SANDY SILTSTONE CLAYEY CM TCTflKIPOlLI J IVjlNC Gray and Dark Ol ive Gray,Moist, F 1 NE SANDY Very Firm,Massive Structure SILTSTONE Continued on Drawing No. 13 PROJECT NO. 79-4- 12F DRIVE ENERGYFT. KIPS/FT.57.2 70.4 74.8 164.4 FIELD IMOISTURE 1% DRY WT. |15.0 17.9 20.4 13.5 BENTON ENGINEERING, INC.DRY DENSITY 1LBS7CU. FT. 1117.9 111.1 103.1 119.3 SHEAR 1RESISTANCE 1KIPS/Sa FT. |5.20 5.69 5.20 +7.45 DRAWING NO. 12 Ul I Ulo 41- 42- _ 43- 44- 45 _lu. 46_ 47 1 48. 49- 50 - 51 _ _ 52 - 53- _ 54_ 56 _ - UICC_| uj S| (n) © ma) 53_iu98=£ 0 ill x*c§§5 ^^^§§£& ^^^s?§&& ^§§§5 vsxv§ §§§8 ^^& ^^^S ^^P 111 11 ^^ ^ *§|§^ ^P SUMMARY SHEET BORINQ NO. 5 ( .Cont. ) Gray and Dark Olive Gray, Moist, Very Firm Approximately Level Irregular C on ta ct, Ye 1 1 ow G ray Brown and Light Gray Brown,w!th Few Rust Stains at 41', SI igh tly Cemented, with Slight Clay Binder, Scattered Lenses of Si Ity Fine to Medium Sand, Merges Yellow Gray Brown and Light Gray Brown, Moist, Very Firm, Slightly Cemented to Cemented, iVith Scattered Thin Cemented Lenses of Silty Fine Sand 3ontact Dips Down 8" to W. Light Gray, Moist, Very Firm, SI ?9htly Cemented to Cemented Light Yellow Brown, Moist, Very Firm, Slightly Cemented to 3emented, Contact Dips Down to 8 to West at 52'. Gray, Moist, Very Firm, Massive Structure FINE SANDY SILTSTONE SILTY FINE SAND SILTY FINE TO MEDIUM SAND SILTY FINE SAND SILTY FINE TO MEDIUM SAND SILTY CLAYSTONE If *i* 123.0 127.9 91.8 FIELDMOISTURE% DRY WT.11.9 8.2 18.5 i*s^& 118.6 11.8 112.3 V £2? 5l2 +7.45 7.08 +7.45 i. PROJECT NO. 79-4- 12F BENTON ENGINEERING, INC. DRAWING NO. 13 HAmerican Geotechnical, Inc. APPENDIX C- LABORATORY TESTING LABORATORY TEST PROCEDURES Moisture Content Determinations Moisture content determinations were made in accordance with ASTM method of test D2216. Particle Size Analysis Particle size analyses were performed in accordance with ASTM method of test D422. Both mechanical and hydrometer procedures were utilized. Atterberg Limits The liquid limit and the plastic limit were performed in accordance with ASTM method of test D4318, Compaction Tests Maximum dry density and optimum moisture content determinations were performed in accordance with ASTM method of test Dl 557. Expansive Soil Testing Expansion tests were performed in accordance with Uniform Building Code 18-2 procedures. Direct Shear Direct shear tests were performed on samples remolded to in-place moisture and density. Soil samples were allowed to soak for about 24 hours while under the confining pressure specified for testing. Consolidated drained conditions were approximated by using a slow, strain-controlled approach, similar to that outlined in ASTM method of test D3080. Sulfate Tests Sulfate tests were performed in accordance with EPA method 375.4. File No. 23280.01 May 31, 2007 LABORATORY DATA SUMMARY SAMPLE LOCATION Sand/Clay Mixture Sanely Fill Soil Clay Pad Soil SO!L TYPE Clayey Sand SiltySand Clay with Sand uses SYMBOLS sc SM CL 1 {%) CLAY PARTICLES 20.7 19.6 27,0 ATTERBERG LIMITS Liquid Limit P.i. 32 — 47 12 NP 30 COMPACTION TEST Max Dry Optimum Density Moisture (PCF) <%) 118,3 117.5 122.2 12,0 13.0 10.5 EXPANSION TEST Expansion Expansion Index Potential 58 — 106 Medium — High T = Shelby Tube Sample R = Ring Sample SC = Sand Cone RM = Remolded Sample I 3n> ^>n' QJ 13 0)n n QJ n p E R C E N T F I N E R B \ \\ E I G H T 100 95 90 85 80 75 70 65 60 55 50 45 40 r 35 30 25 20 15 10 5 0 U.S. SIEVE OPENING IN INCHES I 6 4 3 2 1.5 1 3/4 1/23/8 1 1 1 1! ': 3 ^6 T U.S. SIEVE NUMBERS HYDROMETER 810 1416 jig 30 40 50 70100140200nrr^'T r*1\ * 1" XIV\\\ \ \ \ \\ \ 1M1 1 i s s , \ ^ |N s H =k ^ K. \ >x i^ ' -H-, I \ I i. sn \ \ \1 \i \\ k \ ^ 100 10 1 0.1 0. 0.001 GRAIN SIZE IN MILLIMETERS COBBLES GRAVEL coarse Specimen Identification •a H A B C Specimen Identification A B C fine SAND coarse mediuim fine Classification MC% CLAYEY SAND SC SBLTYSANDSM LEAN CLAY with SAND CL DlOO(mm) ] 4.75 2.00 4.75 D60(mm) 0.13 0.16 0.02 D30(mi 0.006 0.013 0.002 SILT OR CLAY LL 32 NP 47 n) DlO(mm) %Gravel 0.0 0.0 0.0 PROJECT La Cosfa Condominiums PL 20 NP 17 %Sand 55.4 64.0 28.0 JOB NO. DATE PI 12 NP 30 Cc %Silt Cu %Clay 23.9 20.7 16.4 19.6 44.9 27.0 23280. 01 05/15/07 GRADATION CURVES ElAmerican Geotechnical, Inc -C"5c 00 b0_c 00 1 0 "u 03= Normal Pressure (Ksf) Symbols O O O Peak stress Ultimate stress Residual Intact Remolded Initial dry density pcf Initial moisture content % Saturated prior to test Remolded to 90% of M.D.DandO.M.C Kr^l Geotechnical, Inc. Direct Shear Test Plot Sand / Clay Mixture (A) RN' 2328a01 D) ICO 1_ D 0_cco 0>'-i—U 0 0 0 Normal Pressure (Ksf) Symbols O O O Peak stress Ultimate stress Residual Intact Remolded Initial dry density pet Initial moisture content % Saturated prior to test Remolded to 90% of M.D.Dand O.M.C [E0*9[ Geotechnical, Inc. Direct Shear Test Plot 7328001 Sandy Fill Soil (B) F.N. 23280.01 Symbols 0 A 0 A O A Peak stress Ultimate stress Residual | Intact [><] Remolded Initial dry density pcf Initial moisture content % Saturated prior to test Remolded to 90% of M.D.Dand O.M.C Normal Pressure (Ksf) Geotechnical, Inc.pHClay Pad F.N. 23280.01 135 133 131 129 127 125 123 121 119 D R 117Y D 115 E N 113 S j 111 Y 109 P o iQ.y u n d 105 s p 103 r 101 C 99 u b i 97 c F 5 I 93 t 91 89 87 85 83 81 79 77 75C i f/ t ^ 1 ' f' \ \ s t/ \ \ s 4f ' s ^ V \ ^l. \ / \ \ \ \ / \^ ^\ ^•^ . ^ \ \ l. s\ V\-\ \ '• \ \ \h1I\! \ Job No. Project: Sa Descripti( V ^•V\ ( ••\ x. \ * \ 23280.01 Date 05/15/07 La Costa Condominiums mple locatio MI of Materi Test Methoc * \ ^^^\ \\ \ J OF \ \^\ \ n A al sand/clav mixture-greenish/srev sandv clav 1 TESTF Maximum D >timum Wat( CURVESFOR SPEC i ^, v V\ K \^ '• X ^V . \^\ \ ) 5 10 15 20 25 30 WATER CONTENT (Percent) \ \ ASTM D1557-02, "A" RESULTS ry Density 118.3PCF ;r Content 12.0 % OF 100% SATURATIONIFIC GRAVITY EQUAL TO: - 2.80 2.70 2.60 ^k \\ \ \ ^ ^'• ~*K'- \.'••. "T. v •• '• v '• x.•. X\ V '-. \ ]V . N I\ '•.. x T]V N ^V 35 40 45 MOISTURE-DENSITY RELATIONSHIP ^American Geotechnical, Inc F.N. 23280.01 May 2007 r 135 133 131 129 127 125 123 121 119 D R 117Y D 115 E N 113 S ' 111 Y 109 P o 107 n d 105 s p 103 T 101 C 99 u b i 97 c F 95 o 93 t 91 89 87 85 83 81 79 77 75C > ^ / / \ \ /< 4 \ / ~ /\ v\\ \\ ^\\ • v\ \ ^\\ \ / vT \\ ^i. \\ v\ y \ \ \ Job No. Project: Sa Descriptii •N V\ N VS %. k 23280.01 Date 05/15/07 La Costa Condominiums mple locatic an of Materi Test Methoc \ V ^V \\ \ I OF \ \, \ \ n B al sandy fill soil-yellow/brown clayey sand I ASTMD 1557-02, "A" TEST RESULTS Maximum Dry Density 1 17.5 PCF rtimum Water Content 13.0% CURVES OF 100% SATURATIONFOR SPECIFIC GRAVITY EQUAL TO: N, ~ 2-8° -K. 270'v\ k ^. ••- 260 y\ \ \ V •\ x \\\\ \ ^.^ V•.. "T. v•-. ^rv\.. . N. '•• N rs.. \ ^y '-. N PV ) 5 10 15 20 25 30 35 40 45 WATER CONTENT (Percent) MOISTURE-DENSITY RELATIONSHIP ^American Geotechnical, Inc F.N. 23280.01 May 2007 T" 135 133 131 129 127 125 123 121 119 D R 117 Y D 115 E N 113 S { 111 Y 109P u 107 n d 105 s p 103 r 101 C 99 u bi 97 c F 95 o o 93 t 91 89 87 85 83 81 79 77 750 / / ^ ( / \ /Ji \ / \ \ s N /' i \ j £ V _ L / > V v ^ \ \k \\ \ \ \\ l. VV y\ V \ \ s•\\ •\ Job No. Project: Sa Descripti V\ \ s '. V \y \ V ^ ^. \ 23280.01 Date 05/15/07 La Costa Condominiums mple locatic an of Materi Test Metho< \ ^ V I\ \\\ \ I Of \ \ \\ \ in C al clay pad soil-greenish/erey clay 1 ASTMD 1557-02, "A" TEST RESULTS Maximum Dry Density 1 22.2 PCF itimum Water Content 1 0.5 % CURVES OF 100% SATURATION FOR SPECIFIC GRAVITY EQUAL TO: L - 2.80 ~\ 270 ^•A' \^ — 260 '•• x ^.\ \ x \ '••• '• i '•• N \\ \\ V\u '•—• ^\ ^^ %' . Vr~ ••. ^ v. .S.\ V "• s NNXu •• VX'•TJ^- '•• -\•35 10 15 20 25 30 35 40 45 WATER CONTENT (Percent) MOISTURE-DENSITY RELATIONSHIP ^American Geotechnical, Inc | F.N. 23280.01 May 2007 IlAmerican Geotechnical, Inc. APPENDIX D - SLOPE STABILITY SURFICIAL SLOPE STABILITY ANALYSIS Flowlines j LEGEND : Z = Depth of Saturation (feet) a = Slope Angle (degree) -yt= Total Unit Weight of Soil (pcf) 7b = Buoyant Unit Weight of Soil (pcf) <j> = Friction Angle (degree) c = Cohesion (psf) FD = '/2 ZY, sin (2a) FR = Z-yb cos2 a tan $ + c F.S. = FR / FD Force Tending To Cause Movement Force Tending To Resist Movement Factor of Safety SOIL PROPERTIES : c = 125 33 100 a = 62.6 33.7 Case Z= FD = FR = F.S. = 1 1 57.70 128.14 2.22 2 2 115.40 156.28 1.35 3 3 173.10 184.41 1.07 4 4 230.80 212.55 0.92 AMERICAN GEOTECHNICAL INC. 5764 Pacific Center Blvd, Suite 112 San Diego, Ca 92121 Project: LA COSTA CONDOMINIUMS F.N. 23280-01 FIGURE 1 Factor of Safety Summary Cross Section A-A1 B-B1 D-D1 F-F1 i-r J-J1 (slope 1) J-J1 (slope 2) K-K' L-L1 Existing Condition Circular Failure Bishop 1.62 1.12 1.34 1.81 1.75 2.46 n/a 1.26 2.21 Block Failure Spencer 1.51 n/a 2.36 1.94 n/a n/a n/a n/a n/a Back Cut Circular Failure Bishop 1.21 1.29 1.94 1.66 n/a 2.19 2.07 1.39 n/a After Improvement Circular Failure Bishop 1.83 1.90 2.34 2.04 n/a 1.83 1.92 1.91 n/a Block Failure Spencer 1.77 n/a 2.83 1.89 n/a n/a n/a n/a n/a Seismic Bishop 1.32 1.37 1.62 1.50 1.28 1.43 1.46 1.39 1.51 240 r 200 160 CD cg'+—>CO _0 LU Material #: 1 Description: Landslide Cohesion: 460 Phi: 10 Material #: 2 Description: Fill Cohesion: 250 Phi: 33 Material #: 3 Description: Sandstone Cohesion: 600 >ris Material #: 4 Description: Clay Cohesion: 200 Phi: 22 Material #: 5 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 6 Description: Claystone Cohesion: 600 Phi: 35 320 360 400 La Costa Condominiums F.N. 23280.01 File NameA-A' existing conditions case2.gsz 240 r— ^§23 . 200 160 CDCD H— co "5 _0> LU 120 80 40 Material #: 1 Description: Landslide debris Cohesion: 460 Phi: 10 Material #: 2 Description: Fill Cohesion: 250 Phi: 33 Material #: 3 Description: Sandstone Cohesion: 600 Cohesion: 200 Phi: 22 Material #: 5 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 6 Description: Claystone Cohesion: 600 Phi: 35 ' 40 80 120 160 200 240 280 320 360 400 La Costa Condominiums F.N. 23280.01 File NameA-A' existing conditions case2.gsz 240 i- 200 160 (D O 1201 LU 80 40 i 40 80 120 160 11- 200 Material #: 1 Description: Landslide debris Cohesion: 460 Phi: 10 aterial #: 2 Cohesion: 250 Phi: 33 Material #: 3 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 4 Description: Clay Seam Cohesion: 200 Phi: 22 Material #: 5 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 6 Description: Claystone Cohesion: 600 Phi: 35 Material #: 7 Description: Bedrock 320 360240 280 La Costa Condominiums F.N. 23280.01 File NameA-A' existing conditions block failure case2.gsz 1.512 240 -- 40 o •- Material #: 1 Description: Landslide debris Cohesion: 460 Phi: 10 aterial #: 3 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 4 Description: Clay Seam Cohesion: 200 Phi: 22 Material #: 5 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 6 Description: Claystone Cohesion: 600 Phi: 35 Material #: 7 Description: Bedrock 120 160 200 __L 1 280 320 L 360240 280 320 360 400 La Costa Condominiums F.N. 23280.01 File NameA-A' existing conditions block failure case2.gsz 240 200 160 CD 80 40 Material #: 1 Description: Landslide debris Cohesion: 460 Phi: 10 Material #: 2 Description: Fill Cohesion: 250 Phi: 33 Material #: 3 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 5 Description: Sanstone Cohesion: 600 Phi: 35 Material #: 6 Description: Claystone Cohesion: 600 Phi: 35 Material #: 6 La Costa Condominiums F.N. 23280.01 A-A' back cut case 2.gsz 40 80 120 160 200 240 280 320 -L 360 400 240 200 160 CD .2 1201 "-4—'CO _0 LJJ 80 40 Material #: 1 Description: Landslide debris. Cohesion: 460 Phi: 10 Material #: 2 Description: Fill Cohesion: 250 Phi: 33 Material #: 3 Description: Sandstone Cohesion: 600 Phi: 35 Cohesion: 200 Material #: 5 Description: Sanstone Cohesion: 600 Phi: 35 Material #: 6 Description: Claystone Cohesion: 600 Phi: 35 J.208 Material #: 6 La Costa Condominiums F.N. 23280.01 A-A' back cut case 2.gsz 40 80 120 160 200 240 280 320 360 400 240 200 160 CD co I _CD LU 120 80 40 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Landslide Debris Cohesion: 460 Phi: 10 Material #: 3 Description: Sandstone Cohesion: 6j Cohesion: 200 Phi: 22 Material #: 5 Description: Sanstone Cohesion: 600 Phi: 35 Material #: 6 Description: Claystone Cohesion: 600 Phi: 35 Material #: 6 La Costa Condominiums F.N. 23280.01 A-A' with stability buttress case 2.gsz 40 80 120 160 200 240 280 320 [ 360 400 240 r 200 160 CD ro _CD LJJ 80 40 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Landslide Debris Cohesion: 460 Phi: 10 Material #: 3 Description: Sandstone Cohesion: 6j Cohesion: 200 Phi: 22 Material #: 5 Description: Sanstone Cohesion: 600 Phi: 35 Material #: 6 Description: Claystone Cohesion: 600 Phi: 35 Material #: 6 La Costa Condominiums F.N. 23280.01 A-A' with stability buttress case 2.gsz I I j 40 80 120 160 200 240 280 320 360 400 Material #: 1 240 ~ Description: Fill Cohesion: 250 Phi: 33 200 160 0)CD H— O I ®. LU 80 Material #: 2 Description: Landslide Debris Cohesion: 460 Phi: 10 Material #: 3 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 4 Description: Description: Sanstone Cohesion: 600 Phi: 35 Material #: 6 Material #: 6 Description: Claystone Cohesion: 600401- Phi: 35 La Costa Condominiums F.N. 23280.01 A-A' with stability buttress block failure case 2.gsz 40 80 120 160 200 240 280 320 360 400 1.773 200 r CD Co _Q LU Material #: 1 240 — Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Landslide Debris Cohesion: 460 Phi: 10 Material #: 3 Description: Sandstone 160 h Cohesion: 600 Phi: 35 Material #: 4 Description^ 1201 80 40 \— Material Description: Sanstone Cohesion: 600 Phi: 35 Material #: 6 Description: Claystone Cohesion: 600 Phi: 35 40 Material #: 4 Material #: 5 Material #: 6 La Costa Condominiums F.N. 23280.01 A-A' with stability buttress block failure case 2.gsz 120 160 . _ _ J . 200 240 280 320 360 400 240 i— 200 160 <D Co 1_5> LU 120> 80 40 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Landslide Debris Cohesion: 460 Phi: 10 Material #: 3 Description: Sandstone Cohesion: 6j Cohesion: 200 Phi: 22 Material ft: 5 Description: Sanstone Cohesion: 600 Phi: 35 Material ft: 6 Description: Claystone Cohesion: 600 Phi: 35 Material #: 6 La Costa Condominiums F.N. 23280.01 A-A' with stability buttress and seismic coefficient case 2.gsz 40 80 120 160 200 240 280 320 | 360 400 240 200 160 <D O 120 03 _O LLJ Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 3Material #: 2 Description: Landslide Debris Cohesion: 460 Phi: 10 Material #: 3 Description: Sandstone Cohesion: 6 Material #: 5 Material #: 4 Cohesion: 200 Phi: 22 Material #: 6 Material #: 5 Description: Sanstone Cohesion: 600 Phi: 35 Material #: 6 Description: Claystone Cohesion: 600 Phi: 35 La Costa Condominiums F.N. 23280.01 A-A' with stability buttress and seismic coefficient case 2.gsz 120 160 200 240 280 320 360 400 240 Material #: 1 Description: Landslide debris Cohesion: 460 Phi: 10 Material^: 3 Material #: 2 Description: Fill Cohesion: 250 Phi: 33 Material #: 4 LLJ 80 40 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 Material #: 5 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 5 La Costa Condominiums F.N. 23280.01 B-B" existing conditions case 2.gsz 40 80 120 160 200 240 280 320 360 400 * • 240 200 160 CD g 1201 I_CD LU 80 40 Material #: 1 Description: Landslide debris Cohesion: 460 Phi: 10 Material #: 2 Description: Fill Cohesion: 250 Phi: 33 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 Material #: 5 Description: Sandstone Cohesion: 600 Phi: 35 80 Material #: 5 La Costa Condominiums F.N. 23280.01 B-B" existing conditions case 2.gsz 40 120 160 200 240 280 320 360 400 240 |- 200 160 CD CD O 120 o a> LJJ 80 40 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: Material #: 3 Description: Claystone Cohesion: 600 Phi: 35 Material #: 4 Description: Sandstone Cohesion: 600 Phi: 35 La Costa Condominiums F.N. 23280.01 B-B' back cut case 2.gsz 40 80 120 160 200 240 280 320 360 _J 400 240 - 200 - 160 CD O 1201 CO _0> LU 80 40 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 6C Material #: 3 Description: Claystone Cohesion: 600 Phi: 35 Material #: 4 Description: Sandstone Cohesion: 600 Phi: 35 J.286. Material #: 4 La Costa Condominiums F.N. 23280.01 B-B' back cut case 2.gsz 40 80 120 160 200 240 280 320 360 400 240 200 160 CD Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Claystone Cohesion: 600 Phi: 35 Material #: 4 Description: Sandstone Cohesion: 600 Phi: 35 La Costa Condominiums F.N. 23280.01 B-B' with stability buttress case 240 200 160 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Claystone Cohesion: 600 Phi: 35 Material #: 4 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 La Costa Condominiums F.N. 23280.01 B-B' with stability buttress case 2.g 40 80 120 160 200 240 280 320 360 400 0) cg I LU 240 200 160 120 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Claystone Cohesion: 600 Phi: 35 Material #: 4 Description: Sandstone Cohesion: 600 Phi: 35 Material #•: 2 Material #: 3 Material #: 4 La Costa Condominiums F.N. 23280.01 B-B' with stability buttress and seismic coefficic nt case 2.gsz 160 200 240 280 320 360 400 • • • • • • • • • • • • • • * • • * 240 200 160 CD LLJ Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Claystone Cohesion: 600 Phi: 35 Material #: 4 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 4 La Costa Condominiums F.N. 23280.01 B-B' with stability buttress and seismic coe*en,case 2.gsz 40 80 120 160 200 240 280 320 360 400 240 200 160 0) .i 120> 73 _ LU 80 |- 40 Material #: 1 Description: Landslide debris Cohesion: 460 Phi: 10 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Claystone Cohesion: 600 Phi: 35 Material #: 4 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 5 Description: Clay Seam Phi: 22 Material #: 6 Description: Claystone Cohesion: 600 Phi: 35 Material #: 7 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 2 Material #: 3 -MaTefTaTff?" Material #: 5 Material #: 6 Material #: 7 La Costa Condominiums F.N. 23280.01 D-D1 existing conditions case 2.gsz 40 80 120 160 200 240 280 320 360 400 440 480 Material #: 1 Description: Landslide debris. Cohesion: 460 Phi: 10 240 200 160 CD _o LLJ Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Claystone Cohesion: 600 Phi: 35 Material #: 4 Description: Sandstone Cohesion: 600 Phi: 35 Phi: 22 Material #: 6 Description: Claystone Cohesion: 600 Phi: 35 Material #: 2 Material #: 3 Material #: 5 Description: Clay Seam Material #: 5 Material #: 6 Material #: 7 40 i-I Material #: 7 Description: Sandstone Cohesion: 600 Phi: 35 La Costa Condominiums F.N. 23280.01 D-D1 existing conditions case 2.gszi , , 40 80 120 160 200 240 280 320 360 400 440 480 240 Material #: 1 Description: Landslide debris Cohesion: 460 Phi: 10 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Claystone Cohesion: 600 200 - Phi: 35 Material #: 4 Description: Sandstone 160 |— Cohesion: 600 Phi: 35 o> co "•*— ' 03 _0) LJJ 40 Material #: 5 Descripti Cohesion: 200 Phi: 22 Material #: 6 Description: Claystone Cohesion: 600 Phi: 35 Material #: 7 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 -MateTiallf:"4 Material #: 5 Material #: 6 Material #: 7 40 80 120 160 200 240 La Costa Condominiums F.N. 23280.01 D-D' existing conditions block failure case 2.gsz 280 320 360 400 440 480 Material #: 1 Description: Landslide debris Cohesion: 460 Phi: 10 Material #: 2 Description: Sandstone Cohesion: 600 240 — Phi: 35 Material #: 3 Description: Claystone Cohesion: 600 Phi: 35200 160 CD O I _CD UU 40 Material #: 4 Description: Sandstone — Cohesion: 600 Phi: 35 Material #: 5 Descriptl Cohesion: 200 Phi: 22 Material #: 6 Description: Claystone Cohesion: 600 Phi: 35 Material #: 7 Description: Sandstone Cohesion: 600 Phi: 35 2.357 Material #: 2 Material #: 3 -MatefialT:"4" Material #: 5 Material #: 6 Material #: 7 La Costa Condominiums F.N. 23280.01 D-D' existing conditions block failure case 2.gsz 40 80 120 160 200 240 280 320 360 400 440 480 240 Material #: Material #: 2 200 — 160 - (DCD Material #: 1 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 2 Description: Claystone Cohesion: 600 Phi: 35 Material #: 3 Description: Clay Seam Cohesion: 200 Phi: 22 80 120 La Costa Condominiums F.N. 23280.01 D-D1 back cut case 2.gsz 160 200 240 280 320 360 400 440 480 240 r 200 160 Material #: 1 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 2 Description: Claystone Cohesion: 600 Phi: 35 Material #: 3 Description: Clay Seam Cohesion: 200 Phi: 22 J.939 La Costa Condominiums F.N. 23280.01 D-D' back cut case 2.gsz 40 80 160 200 240 280 320 360 400 440 480 240 200 160 Material #: 1 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 2 Description: Claystone Cohesion: 600 Phi: 35 Material #: 3 Description: Clay Seam Cohesion: 200 Phi: 22 Material #: 4 Description: Fill Cohesion: 250 Phi: 33 #:3 Material #: 2 Material #: 1 o"o 40 120 200 240 280 320 La Costa Condominiums F.N. 23280.01 D-D' with stability buttress case £.gsz 360 400 440 480 240 200 160 Material #: 1 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 2 Description: Claystone Cohesion: 600 Phi: 35 Material #: 3 Description: Clay Seam Cohesion: 200 Phi: 22 Material #: 4 Description: Fill Cohesion: 250 Phi: 33 Material #: 3 Material #: 2 Material #: 1 40 H La Costa Condominiums F.N. 23280.01 D-D1 with stability buttress case 2.gsz 40 80 120 160 200 240 280 320 360 400 440 480 240 200 - 160 Material #: 1 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 2 Description: Claystone Cohesion: 600 Phi: 35 Material #: 3 Description: Clay Seam Cohesion: 200 Phi: 22 Material #: 4 Description: Fill Cohesion: 250 Phi: 33 Material #: 3 Material #: 2 Material #: 1 La Costa Condominiums F.N. 23280.01 D-D1 with stability buttress block failure case 120 160 200 240 280 320 360 400 440 480 240 — 200 160 Material #: 1 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 2 Description: Claystone Cohesion: 600 Phi: 35 Material #: 3 Description: Clay Seam Cohesion: 200 Phi: 22 Material #: 4 Description: Fill Cohesion: 250 Phi: 33 #:3Material Material #: 2 Material #: 1 La Costa Condominiums F.N. 23280.01 j D-D' with stability buttress block failure case 2.gsz 80 120 160 200 240 280 320 360 400 440 480 240 r 200 160 CDCD O 120 - CO _0) LLJ Material #: 1 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 2 Description: Claystone Cohesion: 600 Phi: 35 Material #: 3 Description: Clay Seam Cohesion: 200 Phi: 22 Material #: 4 Description: Fill Cohesion: 250 Phi: 33 Material #: 3 Material #: 2 Material #: 1 La Costa Condominiums F.N. 23280.01 D-D' with stability buttress and seismic coefficient case 2.gsz 40 80 120 160 200 240 280 320 360 400 440 480 240 200 160 Material #: 1 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 2 Description: Claystone Cohesion: 600 Phi: 35 Material #: 3 Description: Clay Seam Cohesion: 200 Phi: 22 Material #: 4 Description: Fill Cohesion: 250 Phi: 33 1.619* Material #: 3 Material #: 2 La Costa Condominiums F.N. 23280.01 D-D' with stability buttress and seismic coefficient case 2.gsz 400 440 480 240 r 200 \ V' \> Material #: 4 Description: Sanstone Material #: 3 Material #: 4 Description: Clay Seam Cohesion: 200 Phi: 22 Material #: 6 160 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Clay Seam Cohesion: 200 Phi: 22 Material #: 6 Description: Claystone Cohesion: 600 Phi: 35 J_ 8040 120 160 200 240 La Costa Condominiums F.N. 23280.01 F-F1 existing condition case 2.gsz 280 320 360 J.805* Material #: 1 240 !_ Description: Fill Cohesion: 250 Phi: 33 200 — 160 — CD Co To I LLI Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Clay Seam Cohesion: 200 Phi: 22 Material #: 4 Description: Sanstone 120 80 Material #: Material #: 4 Materi Description: Clay Seam Cohesion: 200 Phi: 22 Material #: 6 Description: Claystone Cohesion: 600 Phi: 35 _L 80 La Costa Condominiums F.N. 23280.01 F-F1 existing condition case 2.gsz 120 160 200 240 280 320 360 240 - 200 - 160 CD _o> UJ 40 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Clay Seam Cohesion: 200 Phi: 22 Material #: 4 Description: Sanstone /laterial #: 5 Description: Clay Seam Cohesion: 200 Phi: 22 Material #: 6 Description: Claystone Cohesion: 600 Phi: 35 -Materiat-#:-3- Mgterial #: 4 Material #: 5 Material #: 6 La Costa Condominiums F.N. 23280.01 F-F1 existing condition block failure case 2,gsz o - 0 40 80 120 160 200 240 280 JL 320 360 240 200 - 160 CDCD O 1201 _CD LJJ 80 40 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Clay Seam Cohesion: 200 Phi: 22 Material #: 4 Description: Sanstone 1.940 Material #: 5 Description: Clay Seam Cohesion: 200 Phi: 22 Material #: 6 Description: Claystone Cohesion: 600 Phi: 35 Material #: 2 Material •#--» Material #: 4 Material #: 5 Material #: 6 La Costa Condominiums F.N. 23280.01 F-F existing condition block failure case 2.gsz 40 80 120 160 200 240 280 320 360 240 200 160 O 120 03 I LU 80 40 0 L 0 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Clay Seam Cohesion: 200 Phi: 22 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 40 80 120 160 240 La Costa Condominiums F.N. 23280.01 F-F' back cut case 2.gsz 320280 360 240 200 160 (T5 -9> LJJ Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Clay Seam Cohesion: 200 Phi: 22 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 80 Material #: 4 40 La Costa Condominiums F.N. 23280.01 F-F' back cut case 2.gsz 200 240 280 L_ 320 360 240 - 200 160 CD(D Co "ro ® LU 120 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Clay Seam Cohesion: 200 Phi: 22 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 80 40 o '1 __. 40 J 80 120 160 200 240 La Costa Condominiums F.N. 23280.01 F-F' with stability buttress case 2.gsz i L ... : 280 320 360 240 r 200 - 160 O <D 40 I Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Clay Seam Cohesion: 200 Phi: 22 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 _._, .1 40 ,2.037 80 120 160 _J 200 M^renai w: i ^••dllffi"f \ ' Kt**l***'tr*t U. OMaterial #: 2 Materis 240 Material #: 4 La Costa Condominiums F.N. 23280.01 F-F' with stability buttress case 2.gsz 280 320 360 240 200 - 160 CD C_o H — >05 _0) LLJ 120 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Clay Seam Cohesion: 200 Phi: 22 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 atenai #: i #:2 •Material #: 3 80 120 240 Material #: 4 La Costa Condominiums F.N. 23280.01 F-F with stability buttress block failure case 2.gsz 280 320 360 240 i- 200 160 h Cg "5 _o> LU 120 80 I Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Clay Seam Cohesion: 200 Phi: 22 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 1.889 160 200 240 Material #: 4 La Costa Condominiums F.N. 23280.01 F-F' with stability buttress block failure case 2.gsz J L : 280 320 360 240 ,— 200 160 O 120 | > UJ 80 40 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Clay Seam Cohesion: 200 Phi: 22 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 40 80 120 I 160 La Costa Condominiums F.N. 23280.01 F-F' with stability buttress and seismic coefficient i _ J L L. t_ 200 240 280 320 sz 360 240 r 200 160 CD 80 — 40 hi 0 L- 0 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Clay Seam Cohesion: 200 Phi: 22 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 _..!_ 40 J.501 Materi Material #: 4 La Costa Condominiums F.N. 23280.01 F-F' with stability buttress and seismic coefficient 120 160 . 1 _. 200 240 280 320 360 240 200 160 CDCD g -*—'CO _CD UJ 120 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Claystone Cohesion: 600 Phi: 35 Material #: 4 Description: Sandstone Cohesion: 600 Phi: 35 La Costa Condominiums F.N. 23280.01 isting condition case 2.gsz 120 160 200 240 280 320 360 400 240 200 160 0) g 120 H—'ro CD Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Claystone Cohesion: 600 Phi: 35 Material #: 4 Description: Sandstone Cohesion: 600 Phi: 35 La Costa Condominiums F.N. 23280.01 isting condition case 2.gsz i-A.: J. _l 160 200 240 280 320 400 240 200 160 CD 3 _0 "ffi Hi 120 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Claystone Cohesion: 600 Phi: 35 Material #: 4 Description: Sandstone Cohesion: 600 Phi: 35 La Costa Condominiums F.N. 23280.01 I-P existing condition and seismic Coefficient case 2.gszsmicpoeffi 40 80 120 320 360 400 J.281 , 240 - 200 160 o> 3 o'-*—>03 [D 120 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Claystone Cohesion: 600 Phi: 35 Material #: 4 Description: Sandstone Cohesion: 600 Phi: 35 La Costa Condominiums F.N. 23280.01 -P existing condition and seismic coefficient case 2.gszmic coemL 40 80 320 360 400 240 — 40 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Fill Cohesion: 250 Phi: 33 Material #: 3 Description: ClaySeam Cohesion: 200 Phi: 22 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 40 Material #: 4 La Costa Condominiums F.N. 23280.01 J-J' existing conditions case 2.gsz 1 _^__.._:___; J •« ._. L 120 160 200 240 280 320 360 400 240 i- 200 — 160 CD 120 _o LU 2.464 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Fill Cohesion: 250 Phi: 33 Material #: 3 Description: ClaySeam Cohesion: 200 Phi: 22 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 Material #: 4 40 La Costa Condominiums F.N. 23280.01 J-J' existing conditions case 2.gsz 40 80 120 160 200 240 280 400 240 r Material #: 2 Material #: 3 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: ClaySeam Cohesion: 200 Phi: 22 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 #: 1 Material #: 4 La Costa Condominiums F.N. 23280.01 J-J' back cut slope 1 case 2.gsz 40 80 120 160 200 240 280 320 360 400 240 - 200 160 - <DCD O 120 -t— '03 LJJ 80> . . . . 2J87 • • • • 9 aterial #: 2 Material #: 3 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: ClaySeam Cohesion: 200 Phi: 22 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 l#: 1 80 120 160 200 240 280 La Costa Condominiums F.N. 23280.01 J-J' back cut slope 1 case 2.gsz 320 360 400 240 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 200 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 160 CDCD g 120 I_CD LJJ 40 Material #: 3 Description: ClaySeam Cohesion: 200 Phi: 22 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 <Vxx>f' •••' :••' .-•' ••' .••' X ••' '.< ,>•' s. •• .* >•' . ' Material #: 4 __._] l_ 40 80 ._ . - J - 120 «•' -•' .< ,•:' i-' >•' .-.' X X •*••' .--' .'' ;•' :-•' .--' .-•' -•' .•'•' x' y K ••' -•' -x -• >ferial #: 1 La Costa Condominiums F.N. 23280.01 J-J' back cut slope 2 case 2.gsz 160 200 240 _ I 280 320 360 400 240 - 200 160 g I _CD LU 120 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: ClaySeam Cohesion: 200 Phi: 22 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 Material #: 2Material #: 3 40 Material #: 4 erial #: 1 0 L- 0 40 80 120 _L 160 200 240 280 La Costa Cone F.N. 23280.01 J-J' back cut slope 2 case 2.gsz _J I J 320 360 400 240 r 40 h Material f; 1' Material #: 4 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Fill Cohesion: 250 Phi: 33 Material #: 3 Description: ClaySeam Cohesion: 200 Phi: 22 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 La Costa Condominiums F.N. 23280.01 J-J' with stability buttress slope 1 case 1 .gsz 40 80 120 160 200 240 280 320 360 400 240 r 200 160 J) O 120 I2UJ 80|> 40 Material #: 1 M Material #: 4 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Fill Cohesion: 250 Phi: 33 Material #: 3 Description: ClaySeam Cohesion: 200 Phi: 22 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 La Costa Condominiums F.N. 23280.01 J-J1 with stability buttress slope 1 case 1 .gsz 40 80 120 160 200 240 280 L 320 360 400 240 r— 200 160 CD Co '-»— »CO _0) LJJ 120 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Fill Cohesion: 250 Phi: 33 Material #: 3 Description: ClaySeam Cohesion: 200 Phi: 22 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 V ..,-• :,/• La Costa Condominiums F.N. 23280.01 J-J' with stability buttress slope 2.gsz 160 200 240 280 320 360 400 CD Cg I_0 UJ Material #: 1 Description: Fill Cohesion: 250 240 r Phi: 33 Material #: 2 Description: Fill Cohesion: 250 200 - Phi: 33 Material #: 3 Description: ClaySeam Cohesion: 200 Phi: 22 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 120 I— 160 J.921 i Material #: 1 ....MalerialJfc-3- Material #: 4 40 h La Costa Condominiums F.N. 23280.01 J-J' with stability buttress slope 2.gsz L .^ i 40 80 120 160 200 240 280 320 360 400 240 r Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Fill Cohesion: 250 Phi: 33 Material #: 3 Description: ClaySeam Cohesion: 200 Phi: 22 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 Material #: 4 La Costa Condominiums F.N. 23280.01 J-J1 with stability buttress slope 1 and seismic coefficient.gsz 200 240 280 320 360 400 240 r 200 160 h CD CD g 120 "-i^ 03 _CD LU 80( 40 aterial #: 1 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Fill Cohesion: 250 Phi: 33 Material #: 3 Description: ClaySeam Cohesion: 200 Phi: 22 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 120 160 Material #: 4 La Costa Condominiums F.N. 23280.01 J-J' with stability buttress slope 1 and seismic coefficient.gsz 200 240 280 320 360 400 240 200 160 0 g 120 11>_ LU 80 > 40 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Fill Cohesion: 250 Phi: 33 Material #: 3 Description: CiaySeam Cohesion: 200 Phi: 22 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 Material #: 1 _..Materiai-#;-S Material #: 4 IL_ 40 80 120 160 La Costa Condominiums F.N. 23280.01 J-J' with stability buttress slope 2 and seismic coefficient.gsz J [ j. L i j 200 240 280 320 360 400 240 r— 200 t- 160 CD O I_Q LJJ 120 40 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Fill Cohesion: 250 Phi: 33 Material #: 3 Description: ClaySeam Cohesion: 200 Phi: 22 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 J.463 La Costa Condominiums F.N. 23280.01 J-J' with stability buttress slope 2 and seismic coefficient.gsz 0L_ 0 40 120 160 200 240 280 320 360 400 240 r Material #: 3 Material #: 4 Material #: 1 Description: Landslide Debris Cohesion: 460 Phi: 10 Material #: 2 Description: Fill Cohesion: 250 Phi: 33 Material #: 3 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 Material #: 5 Description: Sandstone Cohesion: 600 Phi: 35 La Costa Condominiums F.N. 23280.01 •K' existing condition case 2.gsz 240 200 CD £ Cg I_CD LJJ 120 40 Material #: 3 Material #: 4 Material 120 L_ 160 L..-J^ 200 -U.'« 240 Material #: 1 Description: Landslide Debris Cohesion: 460 Phi: 10 Material #: 2 Description: Fill Cohesion: 250 Phi: 33 Material #: 3 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 4 Description: Claystone Cohesion: 600 Phi: 35 Material #: 5 Description: Sandstone Cohesion: 600 Phi: 35 La Costa Condominiums F.N. 23280.01 K-K' existing condition case 2.gsz 320 240 - 200 - CDCDH— Co To I LJJ Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Claystone Cohesion: 600 Phi: 35 Material #: 4 Description: Sandstone Cohesion: 600 Phi: 35 80 120 160 200 240 280 La Costa Condominiums F.N. 23280.01 K-K' back cut case 2.gsz 320 240 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Claystone Cohesion: 600 Phi: 35 Material #: 4 Description: Sandstone Cohesion: 600 Phi: 35 240 280 La Costa Condominiums F.N. 23280.01 K-K' back cut case 2.gsz 320 240 r 200 u 160 CD Co I_o LJJ 120 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Claystone Cohesion: 600 Phi: 35 Material #: 4 Description: Sandstone Cohesion: 600 Phi: 35 80 120 160 200 240 280 La Costa Condominiums F.N. 23280.01 K-K' with stability buttress case 2.gsz I I 320 ^1.909 • ; ; ; 240 200 - CDCD O 120 CO _Q) LU Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Claystone Cohesion: 600 Phi: 35 Material #: 4 Description: Sandstone Cohesion: 600 Phi: 35 40 80 120 160 200 240 La Costa Condominiums F.N. 23280.01 K-K' with stability buttress case 2.gsz 280 320 240 200 - CD CDM— o I_cp UJ Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Claystone Cohesion: 600 Phi: 35 Material #: 4 Description: Sandstone Cohesion: 600 Phi: 35 80 120 160 200 Material #: 4 La Costa Condominiums F.N. 23280.01 K-K' with stability buttress and seismic coefficient case 2.gsz-:i:_. .„ .L: i 240 280 320 240 |- Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Claystone Cohesion: 600 Phi: 35 Material #: 4 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 4 La Costa Condominiums F.N. 23280.01 K-K' with stability buttress and seismic coefficient case 2.gsz 200 240 280 320 240 r— 200 Material #: 1 Description: Fill Cohesion: 250 _ Phi: 33 CDCD O 120> _CD LU Material #:.2Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Claystone Cohesion: 600 Phi: 35 Material #: 4 Description: Sandstone Cohesion: 600 . Phi: 35 Material #: 4 msLa Costa Condomii F.N. 23280.01 L-L' existing condition case 2.gsz 40 80 120 160 200 240 280 240 r 200 160 CD C.g _CD LU 120 40 Material #: 1 Description: Fill < Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Claystone Cohesion: 600 Phi: 35 laterial #: ^^^ Description: SandSWB Cohesion: 600 Phi: 35 Material #: 4 La Costa Condominiums F.N. 23280.01 L-L' existing condition case 2.gsz 40 80 120 160 200 240 280 320 360 240 200 160 0)0) _0>uu 40 Material #: 1 Description: Fill Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 3 Description: Claystone Cohesion: 600 Phi: 35 Material #: 4 Description: Sandstone Cohesion: 600 . Phi: 35 Material #: La Costa Condominiums F.N. 23280.01 L-L' existing condition and seismic coefficient cas J :_.- 120 160 200 240 280 320 360 1.512 240 200 160 Material #: 1 Description: Fill t Cohesion: 250 Phi: 33 Material #: 2 Description: Sandstone Cohesion: 600 Phi: 35 Material #: 2 Material #: 3 Material #: 3 Description: Claystone Cohesion: 600 Phi: 35 Material #: Description: SandsTWW Cohesion: 600 Phi: 35 La Costa Condominiums F.N. 23280.01 L-L' existing condition and seismic coefficient case 2.gsz 160 200 240 280 320 360 HAmerJcan Geotechnical, Inc. APPENDIX E - SEISMIC EVALUATION RESULTS La COStaTEST.OUT *********************** * ** EQFAULT * * ** Version 3.00 * * ************************ DETERMINISTIC ESTIMATION OF PEAK ACCELERATION FROM DIGITIZED FAULTS JOB NUMBER: 23280-0000 DATE: 05-02-2007 JOB NAME: La Costa condos, Lot 185 south Unit 1 CALCULATION NAME: Test Run Analysis FAULT-DATA-FILE NAME: C:\Program Files\EQFAULTl\CDMGFLTE.DAT SITE COORDINATES:SITE LATITUDE: 33.0873SITE LONGITUDE: 117.2570 SEARCH RADIUS: 50 mi ATTENUATION RELATION: 8) Bozorgnia Campbell Niazi (1999) Hor.-soft Rock-Uncor.UNCERTAINTY (M=Median, S=Sigma): S Number of Sigmas: 1.0 DISTANCE MEASURE: cdiSt SCOND: 1Basement Depth: 1.00 km Campbell SSR: 1 Campbell SHR: 0 COMPUTE PEAK HORIZONTAL ACCELERATION FAULT-DATA FILE USED: C:\Program Files\EQFAULTl\CDMGFLTE.DAT MINIMUM DEPTH VALUE (km): 3.0 Page 1 La COStaTEST.OUT EQFAULT SUMMARY DETERMINISTIC SITE PARAMETERS Page 1 ABBREVIATED FAULT NAME ROSE CANYON NEWPORT-INGLEWOOD (Offshore) CORONADO BANK ELSINORE-TEMECULA ELSINORE- JULIAN ELSINORE-GLEN IVY EARTHQUAKE VALLEY PALOS VERDES SAN JACINTO-ANZA SAN JACINTO-SAN JACINTO VALLEY APPROXIMATE DISTANCE mi (km) 6.2( 10.0) 11. 2( 18.0) 21. 1( 33.9) 24. 5( 39.5) 24. 5( 39.5) 38. 8( 62.4) 39. 7( 63.9) 41. 8( 67.2) 47. 3( 76.2) 49. 2( 79.2) ESTIMATED MAX. EARTHQUAKE EVENT MAXIMUM EARTHQUAKE MAG . (Mw) 6.9 6.9 7.4 6.8 7.1 6.8 6.5 7.1 7.2 6.9 PEAK SITE ACCEL, g 0.582 0.368 0.263 0.142 0.178 0.080 0.061 0.092 0.085 0.064 EST. SITE INTENSITY MOD. MERC. X IX IX VIII VIII VII VI VII VII VI -END OF SEARCH- 10 FAULTS FOUND WITHIN THE SPECIFIED SEARCH RADIUS. THE ROSE CANYON FAULT IS CLOSEST TO THE SITE. IT IS ABOUT 6.2 MILES (10.0 km) AWAY. LARGEST MAXIMUM-EARTHQUAKE SITE ACCELERATION: 0.5816 g Page 2 La COStaTEST.OUT *********************** * * * EQFAULT * * ** version 3.00 * * * *********************** DETERMINISTIC ESTIMATION OF PEAK ACCELERATION FROM DIGITIZED FAULTS JOB NUMBER: 23280-0000 DATE: 05-02-2007 JOB NAME: La Costa Condos, Lot 185 South Unit 1 CALCULATION NAME: Test Run Analysis FAULT-DATA-FILE NAME: C:\Program Files\EQFAULTl\CDMGFLTE.DAT SITE COORDINATES:SITE LATITUDE: 33.0873SITE LONGITUDE: 117.2570 SEARCH RADIUS: 50 mi ATTENUATION RELATION: 8) Bozorgnia Campbell Niazi (1999) Hor.-soft Rock-uncor. UNCERTAINTY (M=Median, S=Sigma): M Number of Sigmas: 0.0 DISTANCE MEASURE: cdlSt SCOND: 1 Basement Depth: 1.00 km Campbell SSR: 1 Campbell SHR: 0 COMPUTE PEAK HORIZONTAL ACCELERATION FAULT-DATA FILE USED: C:\Program FileS\EQFAULTl\CDMGFLTE.DAT MINIMUM DEPTH VALUE (km): 3.0 Page 1 La COStaTEST.OUT EQFAULT SUMMARY DETERMINISTIC SITE PARAMETERS Page 1 ABBREVIATED FAULT NAME ROSE CANYON NEWPORT-INGLEWOOD (Offshore) CORONADO BANK ELSINORE-TEMECULA ELSINORE-JULIAN ELSINORE-GLEN IVY EARTHQUAKE VALLEY PALOS VERDES SAN JACINTO-ANZA SAN JACINTO-SAN JACINTO VALLEY APPROXIMATE DISTANCE mi (km) 6.2( 10.0) 11. 2( 18.0) 21. 1( 33.9) 24. 5( 39.5) 24. 5( 39.5) 38. 8( 62.4) 39. 7( 63.9) 41. 8( 67.2) 47. 3( 76.2) 49. 2( 79.2) ESTIMATED MAX. EARTHQUAKE EVENT MAXIMUM EARTHQUAKE MAG . (Mw) 6.9 6.9 7.4 6.8 7.1 6.8 6.5 7.1 7.2 6.9 PEAK SITE ACCEL, g 0.350 0.221 0.158 0.086 0.107 0.048 0.037 0.055 0.051 0.038 EST. SITE INTENSITY MOD. MERC. IX IX VIII VII VII VI V VI VI V -END OF SEARCH- 10 FAULTS FOUND WITHIN THE SPECIFIED SEARCH RADIUS. THE ROSE CANYON FAULT IS CLOSEST TO THE SITE. IT IS ABOUT 6.2 MILES (10.0 km) AWAY. LARGEST MAXIMUM-EARTHQUAKE SITE ACCELERATION: 0.3496 g Page 2 TEST.OUT ************************* * ** EQSEARCH * * ** version 3.00 * * * ************************* ESTIMATION OFPEAK ACCELERATION FROMCALIFORNIA EARTHQUAKE CATALOGS JOB NUMBER: 23280-0000 DATE: 05-02-2007 JOB NAME: La costa Condos, Lot 185 South unit 1 EARTHQUAKE-CATALOG-FILE NAME: ALLQUAKE.DAT MAGNITUDE RANGE:MINIMUM MAGNITUDE: 4.00MAXIMUM MAGNITUDE: 9.00 SITE COORDINATES:SITE LATITUDE: 33.0873SITE LONGITUDE: 117.2570 SEARCH DATES:START DATE: 1900END DATE: 2000 SEARCH RADIUS: 50.0 mi 80.5 km ATTENUATION RELATION: 8) Bozorgnia Campbell Niazi (1999) Hor.-soft Rock-Uncor. UNCERTAINTY (M=Median, s=Sigma): M Number of Sigmas: 0.0 ASSUMED SOURCE TYPE: SS [ss=Strike-slip, DS=Reverse-s~lip, BT=Blind-thrust] SCOND: 1 Depth source: A Basement Depth: 1.00 km Campbell SSR: 1 Campbell SHR: 0 COMPUTE PEAK HORIZONTAL ACCELERATION MINIMUM DEPTH VALUE (km): 3.0 Page 1 TEST.OUT EARTHQUAKE SEARCH RESULTS Page 1 FILE CODE LAT. NORTH LONG. WEST I TIME | DATE (UTC) | DEPTH H M Secj (km) i i QUAKE MAG. SITE ACC.g SITE MM INT. APPROX . DISTANCE mi [km] DMG MGI DMG MGI DMG DMG MGI MGI MGI MGI MGI MGI MGI MGI MGI MGI MGI MGI DMG DMG PAS MGI DMG DMG MGI MGI DMG MGI DMG MGI DMG PAS DMG DMG DMG DMG DMG DMG GSP DMG PAS GSP 33.1670 33.1000 33.1170 33.2000 32.8000 33.5330 33.0000 33.1000 33.1000 33.1000 32 . 7000 33.5000 33.1000 33.5000 33.5000 33.0000 33.1000 32.7000 33.4670 33.488032.9860 33.1000 33.400033.4670 33.1000 32 . 7000 33.1670 33.1000 33.1500 33.1000 33.4670 32.970033.7170 32.8500 33.1670 33.1670 33.4560 33.2670 33.1100 33.7170 32.6790 32.9700 DMG 33.4540 116.4170 116.6000 116.4170 117.0000 117.8330 116.6330 117 . 0000 116.6000 116.6000 116.6000 117.2000 116.8000 116.6000 116.8000 116.8000 116.6000 116.6000 116.7000 12/05/1939 173352.0 08/10/1921 06/04/1940 07/20/1923 01/24/1942 09/21/1942 12/29/1914 02/16/191503/04/1915 05/11/1915 09/08/191511/26/1916 05/28/1917 05/31/1917 06/02/1917 06/11/1917 08/19/1917 03/21/1918 116.5830103/27/1937 116.7770117.8440 116.8000 116.5000116.6330 116.6000 117.2000116.4170 116.6000 116.5830116.6000 116.5830 117.8030117.5170 117.4830 116.5000 116.5000 116.8960 117.0170 116.4000 117.5070 117.1510 117.8100 116.8980 06/12/1959 10/01/1986 06/22/1918 10/11/1918 02/20/1934 02/09/1920 05/20/1920 10/14/1935 08/10/1921 12/02/1935 02/05/1922 03/26/1937 07/14/1986 06/19/1935 02/23/1943 06/23/1932 06/23/1932 06/16/1938 06/07/193504/01/1984 08/06/1938 06/18/1985 04/04/1990 07/29/1936 2151 0.0 103656.0 7 0 0.0 214148.0 7 754.0 10 0 0.0 1330 0.0 1250 0.0 1145 0.0 742 0.0 17 5 0.0 1017 0.0 435 0.0 435 0.0 354 0.0 710 0.0 2325 0.0 528 0.0 11 313.0 201218.6 557 0.0 4 0 0.0 1035 0.0 220 0.0 1330 0.0 1550 0.0 19 6 0.0 319 0.0 1915 0.0 2124 0.0 03246.2 1117 0.0 92112.0 22552.7 23037.1 55916.9 1633 0.0 071702.3 22 056.0 32228.7 085439.3 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 5.7 6.0 0.0 0.0 0.0 0.0 0.00.0 0.0 0.0 0.0 0.0 10.0 0.0 0.0 0.0 0.0 10.0 0.0 11.0 10.0 5.7 6.0 142252.8 10.0 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 0.004 0.005 0.004 0.014 0.005 0.004 0.015 0.005 0.005 0.005 0.008 0.005 0.005 0.005 0.005 0.005 0.005 0.005 0.004 0.005 0.006 0.008 0.0040.004 0.005 0.0080.004 0.005 0.0050.005 0.004 0.0060.004 0.011 0.004 0.004 0.006 0.013 0.004 0.004 0.007 0.006 0.006 I | 48. 9( 78.7) II I IV II I IVIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII 38. 0( 61.2) 48. 6( 78.2) 16. 8( 27.0) 38. 8( 62.5) 47. 4( 76.2) 16. 0( 25.8) 38. 0( 61.2) 38. 0( 61.2) 38. 0( 61.2) 26. 9( 43.4) 38. 8( 62.5) 38. 0( 61.2) 38. 8( 62.5) 38. 8( 62.5) 38. 5( 61.9) 38. 0( 61.2) 41. 9( 67.5) 46. 9( 75.5) 39. 1( 63.0) 34. 7( 55.8) 26. 4( 42.6) 48. 8( 78.5) 44. 5( 71.7) 38. 0( 61.2) 26. 9( 43.4) 48. 9( 78.7) 38. 0( 61.2) 39. 2( 63.1) 38. 0( 61.2) 46. 9( 75.5) 32. 6( 52.5) 46. 0( 74.0) 21. 0( 33.7) 44. 1( 71.0) 44. 1( 71.0) 32. 9( 52.9) 18. 6( 29.9) 49. 6( 79.8) 45. 8( 73.7) 28. 8( 46.4) 33. 0( 53.1) 32. 7( 52.6) Page 2 TEST. OUT OMG DMG DMG DMG DMG DMG PAS PAS DMG DMG 33.4500 33.1670 33.4200 33.4830 33.1000 33.4170 33.7010 32.9450 33.0020 33.7380 116.6830 116.4170 116.4900 116.7000 116.6330 116.5670 116.8370 117.8310 116.4360 117.1870 04/25/1955 07/10/1938 03/29/1937 12/28/1948 02/08/1952 12/22/1950 08/22/1979 07/29/1986 07/02/1957 04/27/1962 25515.0 18 6 0.0 17 316.8 125341.0 174028.0 2 536.0 2 136.3 81741.8 65638.5 91232.1 0.0 0.0 10.0 0.0 0.0 0.0 5.0 10.0 12.8 5.7 4.00 4.00 4.00 4.00 4.00 4.00 4.10 4.10 4.10 4.10 0.005 0.004 0.004 0.004 0.005 0.004 0.004 0.006 0.004 0.004 II I I I II I I II I I 41. 5( 66.8) 48. 9( 78.7) 49. 9( 80.3) 42. 2( 67.9) 36. 1( 58.1) 45. 9( 73.8) 48. 8( 78.5) 34. 6( 55.8) 47. 9( 77.0) 45. 1( 72.6) EARTHQUAKE SEARCH RESULTS Page 2 FILE CODE DMG DMG PAS USG USG PAS GSP GSP GSP DMG DMG PAS PAS DMG PAS DMG DMG MGI GSP DMG PAS PAS PAS DMG DMG DMG DMG DMG DMG DMG DMG DMG DMG PAS DMG MGI PAS DMG MGI LAT. NORTH 33.5080 33.7330 32.6150 33.0170 33.0170 32.7590 33.6320 33.0700 33.6500 33.1670 33.2000 32.9470 32.7140 33.7480 32.9330 33.4000 33.1000 32.7000 32.9850 33.0970 33.0330 32.9450 33.4200 32.7170 33.4670 33.4670 33.6820 33.0000 33.5000 33.7000 33.5000 33.1170 33.5450 33.1380 32.5830 32.8000 32.9900 33.1100 33.5000 LONG. WEST 116.6310 117.4670 117.1520 117.8170 117.8170 117.9060 116.7190 116.8000 116.7400 116.4670 116.7200 117.7360 117 . 9100 117.4790 117 . 8410 116.5670 116.4500 117.2000 117.8180 116.4440 117 . 9440 117.8060 116.6980 117.8330 116.5830 116.5830 117.5530 117 . 0000 116.9170 117.1000 117.0000 116.4170 117.8070 116.5010 117 . 8000 116.8000 117.8490 116.5230 116.8000 DATE 08/11/1967 10/26/1954 10/29/1986 07/16/1986 07/14/1986 10/18/1976 07/19/1999 12/04/1991 12/02/1989 08/01/1960 05/12/1930 01/15/1989 10/18/1976 06/22/1971 07/29/1986 02/04/1953 11/23/1953 04/19/1906 06/21/1995 08/18/1959 02/22/1983 09/07/1984 06/05/1978 11/06/1950 01/04/1938 03/27/1937 07/05/1938 03/03/1906 11/04/1935 06/11/1902 08/08/1925 10/21/1940 10/27/1969 10/10/1984 04/19/1939 08/14/1927 07/13/1986 01/24/1957 03/30/1918 TIME (UTC) H M Sec h 05711.4 162226.0 23815.3 1247 3.7 11112 . 6 172753.1 220927.5 071057.5 231647.8 193930.0 172548.5 153955.2 172652.6 104119.0 81741.6 43616.0 1339 7.0 028 0.0 211736.2 215221.321830.4 11 313.4 16 3 3.9 205546.0 029 0.0 742 0.0 18 655.7 2025 0.0 355 0.0 245 0.0 1013 0.0 64933.0 1316 2.3 212258.9 741 0.0 1448 0.0 14 133.0 205449.9 16 5 0.0 Pac DEPTH (km) 10.7 0.0 14.6 10.0 10.0 13.8 14.0 15.0 14.0 0.0 0.0 6.0 15.1 8.0 10.0 0.0 0.0 0.0 6.0 17.3 10.0 6.0 11.9 0.0 0.0 0.0 10.0 0.0 0.0 0.0 0.0 0.0 6.5 11.6 0.0 0.0 12.0 3.9 0.0 je 3 QUAKE MAG. ^ _ _ 4.10 4.10 4.10 4.11 4.12 4.20 4.20 4.20 4.20 4.20 4.20 4.20 4.20 4.20 4.30 4.30 4.30 4.30 4.30 4.30 4.30 4.30 4.40 4.40 4.50 4.50 4.50 4.50 4.50 4.50 4.50 4.50 4.50 4.50 4.50 4.60 4.60 4.60 4.60 SITE ACC.g 0.004 0.004 0.007 0.007 0.007 0.005 0.004 0.010 0.004 0.005 0.008 0.008 0.005 0.005 0.007 0.005 0.005 0.010 0.008 0.005 0.006 0.008 0.007 0.006 0.006 0.006 0.006 0.023 0.009 0.006 0.010 0.006 0.006 0.006 0.006 0.010 0.009 0.007 0.008 SITE MM INT. I I II II II II I III I II II III II I II II II III II II II II II II II II II IV III II III II II II II III III II III APPROX . DISTANCE mi [km] r 46. 4( 74.6) 46. 2( 74.3) 33. 2( 53.4) 32. 8( 52.7) 32. 8( 52.7) 43. 9( 70.7) 48. 8( 78.5) 26. 5( 42.6) 49. 0( 78.8) 46. 0( 74.0) 32. 0( 51.5) 29. 4( 47.3) 45. 8( 73.7) 47. 4( 76.2) 35. 4( 57.0) 45. 3( 72.9) 46. 7( 75.1) 26. 9( 43.4) 33. 2( 53.5) 47. 0( 75.7) 39. 9( 64.3) 33. 3( 53.5) 39. 6( 63.7) 42. 1( 67.7) 46. 9( 75.5) 46. 9( 75.5) 44. 5( 71.6) 16. 0( 25.8) 34. 6( 55.7) 43. 3( 69.6) 32. 1( 51.7) 48. 6( 78.2) 44. 8( 72.1) 43. 9( 70.6) 47. 0( 75.6) 33. 1( 53.2) 34. 9( 56.2) 42. 5( 68.4) 38. 8( 62.5) TEST. OUT PAS OMG DMG DMG PAS PAS DMG DMG DMG DMG DMG DMG PAS MGI 32.6270 33.5060 33.7250 33.6500 32.7560 33.5580 33.7000 33.7000 33.2000 33.7500 33.7100 33.0000 32.9710 33.2000 117.3770 116.5850 117.4980 116.7500 117.9880 116.6670 117 . 4000 117 . 4000 116.7000 117.0000 116.9250 116.4330 117.8700 116.6000 06/29/1983 05/21/1967 01/03/1956 09/05/1950 01/12/1975 06/15/1982 04/11/1910 05/13/1910 01/01/1920 06/06/1918 09/23/1963 06/04/1940 07/13/1986 10/12/1920 8 836.4 144234.4 02548.9 191956.0 212214.8 234921.3 757 0.0 620 0.0 235 0.0 2232 0.0 144152.6 1035 8.3 1347 8.2 1748 0.0 5.0 19.4 13.7 0.0 15.3 12.2 0.0 0.0 0.0 0.0 16.5 0.0 6.0 0.0 4.60 4.70 4.70 4.80 4.80 4.80 5.00 5.00 5.00 5.00 5.00 5.10 5.30 5.30 0.010 0.007 0.007 0.007 0.007 0.007 0.010 0.010 0.014 0.008 0.009 0.009 0.016 0.014 III II II II II II III III IV III III III IV IV 32. 5( 52.3) 48. 4( 77.8) 46. 2( 74.3) 48. 6( 78.2) 48. 1( 77.5) 47. 1( 75.7) 43. 1( 69.4) 43. 1( 69.4) 33. 1( 53.3) 48. 1( 77.4) 47. 1( 75.7) 48. 1( 77.4) 36. 4( 58.5) 38. 8( 62.4) EARTHQUAKE SEARCH RESULTS Page 3 1 FILE| CODEl LAT. NORTH 1 LONG . | WEST | DATE 1 1 1 H TIME (UTC) M sec DEPTH (km) 1 QUAKE | MAG. | SITE ACC. 9 SITE| MM | INT. | APPROX . DISTANCE mi [km] DMG DMG DMG 33.6990|117.5110|05/31/1938| 83455.4 33.70001117.4000105/15/191011547 0.0 33.7500|117.0000|04/21/1918|223225.0 10.0| 5.50| 0.014 | IV 0.0| 6.001 0.022 | IV 0.0| 6.801 0.036 | V 44.7( 71.9) 43.1( 69.4) 48.1C 77.4) -END OF SEARCH- 109 EARTHQUAKES FOUND WITHIN THE SPECIFIED SEARCH AREA. TIME PERIOD OF SEARCH: 1900 TO 2000 LENGTH OF SEARCH TIME: 101 years THE EARTHQUAKE CLOSEST TO THE SITE IS ABOUT 16.0 MILES C25.8 km) AWAY. LARGEST EARTHQUAKE MAGNITUDE FOUND IN THE SEARCH RADIUS: 6.8 LARGEST EARTHQUAKE SITE ACCELERATION FROM THIS SEARCH: 0.036 g COEFFICIENTS FOR GUTENBERG & RICHTER RECURRENCE RELATION: a-value= 3.569 b-value= 0.900 beta-va"lue= 2.073 TABLE OF MAGNITUDES AND EXCEEDANCES: Earthquake Magnitude 4.0 4.55.05.56.0 Number of Times Exceeded 10932113 2 Cumulative NO. / Year 1.07921 0.31683 0.10891 0.02970 0.01980 Page TEST.OUT 6.5 | 1 I 0.00990 Page 5 2002 Lat/Lon Lookup Output!http://eqint.cr.usgs.gOv/eq-men/cgi-bin/tind-ll-2002-interp-06.c; uses 'or J LOCATION 33.08733 Lat. -117.25703 Long. The interpolated Probabilistic ground motion values, in %g, at the requested point are: 2%PE in 50 yr 48.56 116.17 43 .68 PGA 0.2 sec SA 1.0 sec SA 10%PE in 50 yr 25.87 61.56 24 .14 SEISMIC HAZARD: Hazard by Lat/Lon, 2002 HAmerican Geotechnical, Inc. APPENDIX F - STANDARD GUIDELINES FOR GRADING GEOTECHNICAL GUIDELINES FOR GRADING PROJECTS TABLE OF CONTENTS A. GENERAL 1 B. DEFINITIONS OF TERMS 2 C. OBLIGATIONS OF PARTIES 6 D. SITE PREPARATION 7 E. SITE PROTECTION 8 F. EXCAVATIONS 10 Fl UNSUITABLE MATERIALS 10 F2 CUT SLOPES 10 F3 PAD AREAS 11 G. COMPACTED FILL 12 Gl PLACEMENT 12 G2 MOISTURE 13 G3 FILL MATERIAL 14 G4 FILL SLOPES 15 G5 OFF-SITE FILL 17 H. DRAINAGE 18 I STAKING 19 J. MAINTENANCE 20 Jl LANDSCAPE PLANTS 20 J2 IRRIGATION 20 J3 MAINTENANCE 20 J4 REPAIRS 21 K. TRENCH BACKFILL 22 L STATUS OF GRADING 23 STANDARD DETAILS NOS. 1-9 GEOTECHNICAL GUIDELINES FOR GRADING PROJECTS A. GENERAL Al The guidelines contained herein and the standard details attached hereto represent this firm's standard recommendations for grading and other associated operations on construction projects. These guidelines should be considered a portion of the project specifications. A2 All plates attached hereto shall be considered as part of these guidelines. A3 The Contractor should not vary from these guidelines without prior recommendation by the Geotechnical Consultant and the approval of the Client or his authorized representative. Recommendations by the Geotechnical Consultant and/or Client should not be considered to preclude requirements for approval by the controlling agency prior to the execution of any changes. A4 These Standard Grading Guidelines and Standard Details may be modified and/or superseded by recommendations contained in the text of the preliminary geotechnical report and/or subsequent reports. A5 If disputes arise out of the interpretation of these grading guidelines or standard details, the Geotechnical Consultant shall provide the governing interpretation. Geotechnical Guidelines For Grading Projects Page 2 B. DEFINITIONS OF TERMS Bl ALLUVIUM - unconsolidated detrital deposits resulting from flow of water, including sediments deposited in river beds, canyons, flood plains, lakes, fans at the foot of slopes and estuaries. B2 AS-GRADED (AS-BUILT) - the surface and subsurface conditions at completion of grading. B3 BACKCUT - a temporary construction slope at the rear of earth retaining structures such as buttresses, shear keys, stabilization fills or retaining walls. B4 BACKDRAIN - generally a pipe and gravel or similar drainage system placed behind earth retaining structures such as buttresses, stabilization fills and retaining walls. B5 BEDROCK - a more or less solid, relatively undisturbed rock in place either at the surface or beneath superficial deposits of soil. B6 BENCH - a relatively level step and near vertical rise excavated into sloping ground on which fill is to be placed. B7 BORROW (Import) - any fill material hauled to the project site from off-site areas. B8 BUTTRESS FILL - a fill mass, the configuration of which is designed by engineering calculations to stabilize a slope exhibiting adverse geologic features. A buttress is generally specified by minimum key width and depth and by maximum backcut angle. A buttress normally contains a backdrain system. B9 CIVIL ENGINEER - the Registered Civil Engineer or consulting firm responsible for preparation of the grading plans, surveying and verifying as-graded topographic conditions. BIO CLIENT - the Developer or his authorized representative who is chiefly in charge of the project. He shall have the responsibility of reviewing the findings and recommendations made by the Geotechnical Consultant and shall authorize the Contractor and/or other consultants to perform work and/or provide services. B11 COLLUVIUM - generally loose deposits usually found near the base of slopes and brought there chiefly by gravity through slow continuous downhill creep (also see Slope Wash). B12 COMPACTION - is the densification of a fill by mechanical means. B13 CONTRACTOR - a person or company under contract or otherwise retained by the Client to perform demolition, grading and other site improvements. Geotechnical Guidelines For Grading Projects PageS B14 DEBRIS - all products of clearing, grubbing, demolition, contaminated soil material unsuitable for reuse as compacted fill and/or any other material so designated by the Geotechnical Consultant. B15 ENGINEERING GEOLOGIST - a Geologist holding a valid certificate of registration in the specialty of Engineering Geology. B16 ENGINEERED FILL - a fill of which the Geotechnical Consultant or his representative, during grading, has made sufficient tests to enable him to conclude that the fill has been placed in substantial compliance with the recommendations of the Geotechnical Consultant and the governing agency requirements. B17 EROSION - the wearing away of the ground surface as a result of the movement of wind, water and/or ice. B18 EXCAVATION - the mechanical removal of earth materials. B19 EXISTING GRADE - the ground surface configuration prior to grading. B20 FELL - any deposits of soil, rock, soil-rock blends or other similar materials placed by man. B21 FINISH GRADE - the ground surface configuration at which time the surface elevations conform to the approved plan. B22 GEOFABRIC - any engineering textile utilized in geotechnical applications including subgrade stabilization and filtering. B23 GEOLOGIST - a representative of the Geotechnical Consultant educated and trained in the field of geology. B24 GEOTECHNICAL CONSULTANT - the Geotechnical Engineering and Engineering Geology consulting firm retained to provide technical services for the project. For the purpose of these guidelines, observations by the Geotechnical Consultant include observations by the Soil Engineer, Geotechnical Engineer, Engineering Geologist and those performed by persons employed by and responsible to the Geotechnical Consultants. B25 GEOTECHNICAL ENGINEER - a licensed Civil Engineer who applies scientific methods, engineering principles and professional experience to the acquisition, interpretation and use of knowledge of materials of the earth's crust for the evaluation of engineering problems. Geotechnical Engineering encompasses many of the engineering aspects of soil mechanics, rock mechanics, geology, geophysics, hydrology and related sciences. Geotechnical Guidelines For Grading Projects Page 4 B26 GRADING - any operation consisting of excavation, filling or combinations thereof and associated operations. B27 LANDSLIDE DEBRIS - material, generally porous and of low density, produced from instability of natural or man-made slopes. B28 MAXIMUM DENSITY - standard laboratory test for maximum dry unit weight. Unless otherwise specified, the maximum dry unit weight shall be determined in accordance with ASTM Method of Test D 1557-78. B29 OPTIMUM MOISTURE - test moisture content at the maximum density. B30 RELATIVE COMPACTION - the degree of compaction (expressed as a percentage) of dry unit weight of a material as compared to the maximum dry unit weight of the material. B31 ROUGH GRADE - the ground surface configuration at which time the surface elevations approximately conform to the approved plan. B32 SITE - the particular parcel of land where grading is being performed. B33 SHEAR KEY - similar to buttress, however, it is generally constructed by excavating a slot within a natural slope in order to stabilize the upper portion of the slope without grading encroaching into the lower portion of the slope. B34 SLOPE - is an inclined ground surface the steepness of which is generally specified as a ratio of horizontal:vertical (e.g., 2:1). B35 SLOPE WASH - soil and/or rock material that has been transported down a slope by mass wasting assisted by runoff water not confined by channels (also see Colluvium). B36 SOIL - naturally occurring deposits of sand, silt, clay, etc. or combinations thereof. B37 SOIL ENGINEER - licensed Civil Engineer experienced in soil mechanics (also see Geotechnical Engineer). B38 STABILIZATION FILL - a fill mass, the configuration of which is typically related to slope height and is specified by the standards of practice for enhancing the stability of locally adverse conditions. A stabilization fill is normally specified by minimum key width and depth and by maximum backcut angle. A stabilization fill may or may not have a backdrain system specified. Geotechnical Guidelines For Grading Projects PageS B39 SUBDRAIN - generally a pipe and gravel or similar drainage system placed beneath a fill in the alignment of canyons or former drainage channels. B40 SLOUGH - loose, noncompacted fill material generated during grading operations. B41 TAILINGS - non-engineered fill which accumulates on or adjacent to equipment haul-roads. B42 TERRACE - relatively level step constructed in the face of a graded slope surface for drainage control and maintenance purposes. B43 TOPSOIL - the presumably fertile upper zone of soil which is usually darker in color and loose. B44 WINDROW - a string of large rock buried within engineered fill in accordance with guidelines set forth by the Geotechnical Consultant. Geotechnical Guidelines For Grading Projects Page 6 C. OBLIGATIONS OF PARTIES Cl The Geotechnical Consultant should provide observation and testing services and should make evaluations to advise the Client on geotechnical matters. The geotechnical Consultant should report his findings and recommendations to the Client or his authorized representative. C2 The Client should be chiefly responsible for all aspects of the project. He or his authorized representative has the responsibility of reviewing the findings and recommendations of the Geotechnical Consultant. He shall authorize or cause to have authorized the Contractor and/or other consultants to perform work and/or provide services. During grading the Client or his authorized representative should remain on-site or should remain reasonably accessible to all concerned parties in order to make decisions necessary to maintain the flow of the project. C3 The Contractor should be responsible for the safety of the project and satisfactory completion of all grading and other associated operations on construction projects, including, but not limited to, earth work in accordance with the project plans, specifications and controlling agency requirements. During grading, the Contractor or his authorized representative should remain on-site. Overnight and on days off, the Contractor should remain accessible. Geotechnical Guidelines For Grading Projects Page? D. SITE PREPARATION Dl The Client, prior to any site preparation or grading, should arrange and attend a meeting among the Grading Contractor, the Design Engineer, the Geotechnical Consultant, representatives of the appropriate governing authorities as well as any other concerned parties. All parties should be given at least 48 hours notice. D2 Clearing and grubbing should consist of the removal of vegetation such as brush, grass, woods, stumps, trees, roots of trees and otherwise deleterious natural materials from the areas to be graded. Clearing and grubbing should extend to the outside of all proposed excavation and fill areas. D3 Demolition should include removal of buildings, structures, foundations, reservoirs, utilities (including underground pipelines, septic tanks, leach fields, seepage pits, cisterns, mining shafts, tunnels, etc.) and other man-made surface and subsurface improvements from the areas to be graded. Demolition of utilities should include proper capping and/or rerouting pipelines at the project perimeter and cutoff and capping of wells in accordance with the requirements of the governing authorities and the recommendations of the Geotechnical Consultant at the time of demolition. D4 Trees, plants or man-made improvements not planned to be removed or demolished should be protected by the Contractor from damage. D5 Debris generated during clearing, grubbing and/or demolition operations should be wasted from areas to be graded and disposed off-site. Clearing, grubbing and demolition operations should be performed under the observation of the Geotechnical Consultant. D6 The Client or Contractor should obtain the required approvals from the controlling authorities for the project prior, during and/or after demolition, site preparation and removals, etc. The appropriate approvals should be obtained prior to proceeding with grading operations. Geotechnical Guidelines For Grading Projects PageS SITE PROTECTION El Protection of the site during the period of grading should be the responsibility of the Contractor. Unless other provisions are made in writing and agreed upon among the concerned parties, completion of a portion of the project should not be considered to preclude that portion or adjacent areas from the requirements for site protection until such time as the entire project is complete as identified by the Geotechnical Consultant, the Client and the regulating agencies. E2 The Contractor should be responsible for the stability of all temporary excavations. Recommendations by the Geotechnical Consultant pertaining to temporary excavations (e.g., backcuts) are made in consideration of stability of the completed project and, therefore, should not be considered to preclude the responsibilities of the Contractor. Recommendations by the Geotechnical Consultant should not be considered to preclude more restrictive requirements by the regulating agencies. E3 Precautions should be taken during the performance of site clearing, excavations and grading to protect the work site from flooding, ponding or inundation by poor or improper surface drainage. Temporary provisions should be made during the rainy season to adequately direct surface drainage away from and off the work site. Where low areas cannot be avoided, pumps should be kept on hand to continually remove water during periods of rainfall. E4 During periods of rainfall, plastic sheeting should be kept reasonably accessible to prevent unprotected slopes from becoming saturated. Where necessary during periods of rainfall, the Contractor should install checkdams, desilting basins, rip-rap, sand bags or other devices or methods necessary to control erosion and provide safe conditions. E5 During periods of rainfall, the Geotechnical Consultant should be kept informed by the Contractor as to the nature of remedial or preventative work being performed (e.g., pumping, placement of sandbags or plastic sheeting, other labor, dozing, etc.). E6 Following periods of rainfall, the Contractor should contact the Geotechnical Consultant and arrange a walkover of the site in order to visually assess rain related damage. The Geotechnical Consultant may also recommend excavations and testing in order to aid in his assessments. At the request of the Geotechnical Consultant, the Contractor shall make excavations in order to evaluate the extent of rain related-damage. E7 Rain-related damage should be considered to include, but may not be limited to, erosion, silting, saturation, swelling, structural distress and other adverse conditions identified by the Geotechnical Consultant. Soil adversely affected should be classified as Unsuitable Materials and should be subject to overexcavation and replacement with compacted fill or other remedial grading as recommended by the Geotechnical Consultant. Geotechnical Guidelines For Grading Projects Page 9 E8 Relatively level areas, where saturated soils and/or erosion gullies exist to depths of greater than 1.0 foot, should be overexcavated to unaffected, competent material. Where less than 1.0 foot in depth, unsuitable materials may be processed in-place to achieve near-optimum moisture conditions, then thoroughly recompacted in accordance with the applicable specifications. If the desired results are not achieved, the affected materials should be overexcavated, then replaced in accordance with the applicable specifications. E9 In slope areas, where saturated soil and/or erosion gullies exist to depths of greater than 1.0 foot, they should be overexcavated and replaced as compacted fill in accordance with the applicable specifications. Where affected materials exist to depths of 1.0 foot or less below proposed finished grade, remedial grading by moisture conditioning in-place, followed by thorough recompaction in accordance with the applicable grading guidelines herein may be attempted. If the desired results are not achieved, all affected materials should be overexcavated and replaced as compacted fill in accordance with the slope repair recommendations herein. As field conditions dictate, other slope repair procedures may be recommended by the Geotechnical Consultant. Geotechnical Guidelines For Grading Projects Page 10 F. EXCAVATIONS Fl UNSUITABLE MATERIALS Fl.l Materials which are unsuitable should be excavated under observation and recommendations of the Geotechnical Consultant. Unsuitable materials include, but may not be limited to, dry, loose, soft, wet, organic compressible natural soils and fractured, weathered, soft bedrock and nonengineered or otherwise deleterious fill materials. F1.2 Material identified by the Geotechnical Consultant as unsatisfactory due to it's moisture condition should be overexcavated, watered or dried, as needed, and thoroughly blended to a uniform near optimum moisture condition prior to placement as compacted fill. F2 CUT SLOPES F2.1 Unless otherwise recommended by the Geotechnical Consultant and approved by the regulating agencies, permanent cut slopes should not be steeper than 2:1 (horizontal: vertical). F2.2 If excavations for cut slopes expose loose, cohesionless, significantly fractured or otherwise unsuitable material, overexcavation and replacement of the unsuitable materials with a compacted stabilization fill should be accomplished as recommended by the Geotechnical Consultant. Unless otherwise specified by the Geotechnical Consultant, stabilization fill construction should conform to the requirements of the Standard Details. F2.3 The Geotechnical Consultant should review cut slopes during excavation. The Geotechnical Consultant should be notified by the contractor prior to beginning slope excavations. F2.4 If, during the course of grading, adverse or potentially adverse geotechnical conditions are encountered which were not anticipated in the preliminary report, the Geotechnical Consultant should explore, analyze and make recommendations to treat these problems. F2.5 When cut slopes are made in the direction of the prevailing drainage, a non-erodible diversion swale (brow ditch) should be provided at the top-of-cut. Geotechnical Guidelines For Grading Projects Page 11 F3 PAD AREAS F3.1 All lot pad areas, including side yard terraces, above stabilization fill or buttresses should be overexcavated to provide for a minimum of 3 feet (refer to Standard Details) of compacted fill over the entire pad area. Pad areas with both fill and cut materials exposed and pad areas containing both very shallow (less than 3 feet) and deeper fill should be overexcavated to provide for a uniform compacted fill blanket with a minimum of 3 feet in thickness (refer to Standard Details). Cut areas exposing significantly varying material types should also be overexcavated to provide for at least a 3-foot thick compacted fill blanket. Geotechnical conditions may require greater depth of overexcavation. The actual depth should be delineated by the Geotechnical Consultant during grading. F3.2 For pad areas created above cut or natural slopes, positive drainage should be established away from the top-of-slope. This may be accomplished utilizing a berm and/or an appropriate pad gradient. A gradient in soil areas away from the top-of- slopes of 2 percent or greater is recommended. Geotechnical Guidelines For Grading Projects Page 12 G. COMPACTED FILL All fill materials should be compacted as specified below or by other methods specifically recommended by the Geotechnical Consultant. Unless otherwise specified, the minimum degree of compaction (relative compaction) should be 90 percent of the laboratory maximum density. Gl PLACEMENT Gl. 1 Prior to placement of compacted fill, the Contractor should request a review by the Geotechnical Consultant of the exposed ground surface. Unless otherwise recommended, the exposed ground surface should then be scarified (six inches minimum), watered or dried as needed, thoroughly blended to achieve near optimum moisture conditions, then thoroughly compacted to a minimum of 90 percent of the maximum density. The review by the Geotechnical Consultant should not be considered to preclude requirement of inspection and approval by the governing agency. Gl .2 Compacted fill should be placed in thin horizontal lifts not exceeding eight inches in loose thickness prior to compaction. Each lift should be watered or dried as needed, thoroughly blended to achieve near optimum moisture conditions then thoroughly compacted by mechanical methods to a minimum of 90 percent of laboratory maximum dry density. Each lift should be treated in a like manner until the desired finished grades are achieved. G1.3 The Contractor should have suitable and sufficient mechanical compaction equipment and watering apparatus on the job site to handle the amount of fill being placed in consideration of moisture retention properties of the materials. If necessary, excavation equipment should be "shut down" temporarily in order to permit proper compaction of fills. Earth moving equipment should only be considered a supplement and not substituted for conventional compaction equipment. Gl.4 When placing fill in horizontal lifts adjacent to areas sloping steeper than 5:1 (horizontal:vertical), horizontal keys and vertical benches should be excavated into the adjacent slope area. Keying and benching should be sufficient to provide at least six-foot wide benches and a minimum of four feet of vertical bench height within the firm natural ground, firm bedrock or engineered compacted fill. No compacted fill should be placed in an area subsequent to keying and benching until the area has been reviewed by the Geotechnical Consultant. Material generated by the benching operation should be moved sufficiently away from the bench area to allow for the recommended review of the horizontal bench prior to placement of fill. Typical keying and benching details have been included within the accompanying Standard Details. Geotechnical Guidelines For Grading Projects Page 13 G1.5 Within a single fill area where grading procedures dictate two or more separate fills, temporary slopes (false slopes) may be created. When placing fill adjacent to a false slope, benching should be conducted in the same manner as above described. At least a 3-foot vertical bench should be established within the firm core of adjacent approved compacted fill prior to placement of additional fill. Benching should proceed in at least 3-foot vertical increments until the desired finished grades are achieved. Gl .6 Fill should be tested for compliance with the recommended relative compaction and moisture conditions. Field density testing should conform to ASTM Method of Test D1556-64, D2922-78 and/or D2937-71. Tests should be provided for about every two vertical feet or 1,000 cubic yards of fill placed. Actual test interval may vary as field conditions dictate. Fill found not to be in conformance with the grading recommendations should be removed or otherwise handled as recommended by the Geotechnical Consultant. G1.7 The Contractor should assist the Geotechnical Consultant and/or his representative by digging test pits for removal determinations and/or for testing compacted fill. Gl .8 As recommended by the Geotechnical Consultant, the Contractor should "shut down" or remove grading equipment from an area being tested. Gl .9 The Geotechnical Consultant should maintain a plan with estimated locations of field tests. Unless the client provides for actual surveying of test locations, the estimated locations by the Geotechnical Consultant should only be considered rough estimates and should not be utilized for the purpose of preparing cross sections showing test locations or in any case for the purpose of after-the-fact evaluating of the sequence of fill placement. G2 MOISTURE G2.1 For field testing purposes, "near optimum" moisture will vary with material type and other factors including compaction procedure. "Near optimum" may be specifically recommended in Preliminary Investigation Reports and/or may be evaluated during grading. As a preliminary guideline "near optimum" should be considered from one percent below to three percent above optimum. G2.2 Prior to placement of additional compacted fill following an overnight or other grading delay, the exposed surface or previously compacted fill should be processed by scarification, watered or dried as needed, thoroughly blended to near-optimum moisture conditions, then recompacted to a minimum of 90 percent of laboratory maximum dry density. Where wet or other dry or other unsuitable materials exist to depths of greater than one foot, the unsuitable materials should be overexcavated. Geotechnical Guidelines For Grading Projects Page 14 G2.3 Following a period of flooding, rainfall or overwatering by other means, no additional fill should be placed until damage assessments have been made and remedial grading performed as described under Section E6 herein. G3 FILL MATERIAL G3.1 Excavated on-site materials which are acceptable to the Geotechnical Consultant may be utilized as compacted fill, provided trash, vegetation and other deleterious materials are removed prior to placement. G3.2 Where import materials are required for use on-site, the Geotechnical Consultant should be notified at least 72 hours in advance of importing, in order to sample and test materials from proposed borrow sites. No import materials should be delivered for use on-site without prior sampling and testing by the Geotechnical Consultant. G3.3 Where oversized rock or similar irreducible material is generated during grading, it is recommended, where practical, to waste such material off-site or on-site in areas designated as "nonstructural rock disposal areas". Rock placed in disposal areas should be placed with sufficient fines to fill voids. The rock should be compacted in lifts to an unyielding condition. The disposal area should be covered with at least three feet of compacted fill which is free of oversized material. The upper three feet should be placed in accordance with the guidelines for compacted fill herein. G3.4 Rocks 12 inches in maximum dimension and smaller may be utilized within the compacted fill, provided they are placed in such a manner that nesting of the rock is avoided. Fill should be placed and thoroughly compacted over and around all rock. The amount of rock should not exceed 40 percent by dry weight passing the 3/4-inch sieve size. The 12-inch and 40 percent recommendations herein may vary as field conditions dictate. G3.5 During the course of grading operations, rocks or similar irreducible materials greater than 12 inches maximum dimension (oversized material), may be generated. These rocks should not be placed within the compacted fill unless placed as recommended by the Geotechnical Consultant. G3.6 Where rocks or similar irreducible materials of greater than 12 inches but less than four feet of maximum dimension are generated during grading, or otherwise desired to be placed within an engineered fill, special handling in accordance with the accompanying Standard Details is recommended. Rocks greater than four feet should be broken down or disposed off-site. Rocks up to four feet maximum dimension should not be placed in the upper 10 feet of any fill and should not be closer than 20 feet to any slope face. These recommendations could vary as locations of improvements dictate. Geotechnical Guidelines For Grading Projects Page 15 Where practical, oversized material should not be placed below areas where structures or deep utilities are proposed. Oversized material should be placed in windrows on a clean, overexcavated or unyielding compacted fill or firm natural ground surface. Select native or imported granular soil (S.E. 30 or higher) should be placed and thoroughly flooded over and around all windrowed rock, such that voids are filled. Windrows of oversized material should be staggered so that successive strata of oversized material are not in the same vertical plane. The Contractor should be aware that the placement of rock in windrows will significantly slow the grading operation and may require additional equipment and/or special equipment. G3.7 It may be possible to dispose of individual larger rock as field conditions dictate and as recommended by the Geotechnical Consultant at the time of placement. G3.8 Material that is considered unsuitable by the Geotechnical Consultant should not be utilized in the compacted fill. G3.9 During grading operations, placing and mixing the materials from the cut and/or borrow areas may result in soil mixtures which possess unique physical properties. Testing may be required of samples obtained directly from the fill areas in order to verify conformance with the specifications. Processing of these additional samples may take two or more working days. The contractor may elect to move the operation to other areas within the project, or may continue placing compacted fill pending laboratory and field test results. Should he elect the second alternative, fill placed is done so at the Contractor's risk. G3.10 Any fill placed in areas not previously reviewed and evaluated by the Geotechnical Consultant, and/or in other areas, without prior notification to the Geotechnical Consultant may require removal and recompaction at the Contractor's expense. Determination of overexcavations should be made upon review of field conditions by the Geotechnical Consultant. G4 FILL SLOPES G4.1 Unless otherwise recommended by the Geotechnical Consultant and approved by the regulating agencies, permanent fill slopes should not be steeper than 2:1 (horizontal: vertical). Geotechnical Guidelines For Grading Projects Page 16 G4.2 Except as specifically recommended otherwise or as otherwise provided for in these grading guidelines (Reference G4.3), compacted fill slopes should be overbuilt and cut back to grade, exposing the firm, compacted fill inner core. The actual amount of overbuilding may vary as field conditions dictate. If the desired results are not achieved, the existing slopes should be overexcavated and reconstructed under the guidelines of the Geotechnical Consultant. The degree of overbuilding shall be increased until the desired compacted slope surface condition is achieved. Care should be taken by the Contractor to provide thorough mechanical compaction to the outer edge of the overbuilt slope surface. G4.3 Although no construction procedure produces a slope free from risk of future movement, overfilling and cutting back of slope to a compacted inner core is, given no other constraints, the most desirable procedure. Other constraints, however, must often be considered. These constraints may include property line situations, access, the critical nature of the development and cost. Where such constraints are identified, slope face compaction on slopes of 2:1 or flatter may be attempted as a second best alternative by conventional construction procedures including backrolling techniques upon specific recommendation by the Geotechnical Consultant. Fill placement should proceed in thin lifts, (i.e., six to eight inch loose thickness). Each lift should be moisture conditioned and thoroughly compacted. The desired moisture condition should be maintained and/or re-established, where necessary, during the period between successive lifts. Selected lifts should be tested to ascertain that desired compaction is being achieved. Care should be taken to extend compactive effort to the outer edge of the slope. Each lift should extend horizontally to the desired finished slope surface or more as needed to ultimately establish desired grades. Grade during construction should not be allowed to roll off at the edge of the slope. It may be helpful to elevate slightly the outer edge of the slope. Slough resulting from the placement of individual lifts should not be allowed to drift down over previous lifts. At intervals not exceeding four feet in vertical slope height or the capability of available equipment, whichever is less, fill slopes should be thoroughly backrolled utilizing a conventional sheepsfoot-type roller. Care should be taken to maintain the desired moisture conditions and/or reestablishing same as needed prior to backrolling. Upon achieving final grade, the slopes should again be moisture conditioned and thoroughly backrolled. The use of a side-boom roller will probably be necessary and vibratory methods are strongly recommended. Without delay, so as to avoid (if possible) further moisture conditioning, the slopes should then be grid-rolled to achieve a relatively smooth surface and uniformly compact condition. Geotechnical Guidelines For Grading Projects Page 17 In order to monitor slope construction procedures, moisture and density tests should be taken at regular intervals. Failure to achieve the desired results will likely result in a recommendation by the Geotechnical Consultant to overexcavate the slope surfaces followed by reconstruction of the slopes utilizing over-filling and cutting back procedures and/or further attempt at the conventional backrolling approach. Other recommendations may also be provided which would be commensurate with field conditions. G4.4 Where placement of fill above a natural slope or above a cut slope is proposed, the fill slope configuration as presented in the accompanying Standard Details should be adopted. G4.5 For pad areas above fill slopes, positive drainage should be established away from the top-of-slope. This may be accomplished utilizing a berm and pad gradients of at least 2 percent in soil areas. G5 OFF-SITE FILL G5.1 Off-site fill should be treated in the same manner as recommended in these specifications for site preparation, excavation, drains, compaction, etc. G5.2 Off-site canyon fill should be placed in preparation for future additional fill, as shown in the accompanying Standard Details. G5.3 Off-site fill subdrains temporarily terminated (up canyon) should be surveyed for future relocation and connection. Geotechnical Guidelines For Grading Projects Page 18 H. DRAINAGE HI Canyon subdrain systems specified by the Geotechnical Consultant should be installed in accordance with the Standard Details. H2 Typical subdrains for compacted fill buttresses, slope stabilizations or sidehill masses, should be installed in accordance with the specifications of the accompanying Standard Details. H3 Roof, pad and slope drainage should be directed away from slopes and areas of structures to suitable disposal areas via non-erodible devices (i.e., gutters, downspouts, concrete swales). H4 For drainage over soil areas immediately away from structures, (i.e., within four feet) a minimum of 5 percent gradient should be maintained. Pad drainage of at least 2 percent should be maintained over soil areas. H5 Drainage patterns established at the time of fine grading should be maintained throughout the life of the project. Property owners should be made aware that altering drainage patterns can be detrimental to slope stability and foundation performance. Geotechnical Guidelines For Grading Projects Page 19 STAKING 11 In all fill areas, the fill should be compacted prior to the placement of the stakes. This particularly is important on fill slopes. Slope stakes should not be placed until the slope is thoroughly compacted (backrolled). If stakes must be placed prior to the completion of compaction procedures, it must be recognized that they will be removed and/or demolished at such time as compaction procedures resume. 12 In order to allow for remedial grading operations, which could include overexcavations or slope stabilization, appropriate staking offsets should be provided. For finished slope and stabilization backcut areas, we recommend at least a 10-foot setback from proposed toes and tops-of-cut. Geotechnical Guidelines For Grading Projects Page 20 J. MAINTENANCE Jl LANDSCAPE PLANTS In order to enhance surficial slope stability, slope planting should be accomplished at the completion of grading. Slope planting should consist of deep-rooting vegetation requiring little watering. Plants native to the southern California area and plants relative to native plants are generally desirable. Plants native to other semi-arid and arid areas may also be appropriate. A Landscape Architect would be the best party to consult regarding actual types of plants and planting configuration. J2 IRRIGATION J2.1 Irrigation pipes should be anchored to slope faces, not placed in trenches excavated into slope faces. J2.2 Slope irrigation should be minimized. If automatic timing devices are utilized on irrigation systems, provisions should be made for interrupting normal irrigation during periods of rainfall. J2.3 Though not a requirement, consideration should be given to the installation of near- surface moisture monitoring control devices. Such devices can aid in the maintenance of relatively uniform and reasonably constant moisture conditions. J2.4 Property owners should be made aware that overwatering of slopes is detrimental to slope stability. J3 MAINTENANCE J3.1 Periodic inspections of landscaped slope areas should be planned and appropriate measures should be taken to control weeds and enhance growth of the landscape plants. Some areas may require occasional replanting and/or reseeding. J3.2 Terrace drains and downdrains should be periodically inspected and maintained free of debris. Damage to drainage improvements should be repaired immediately. J3.3 Property owners should be made aware that burrowing animals can be detrimental to slope stability. A preventative program should be established to control burrowing animals. Geotechnical Guidelines For Grading Projects Page 21 J3.4 As a precautionary measure, plastic sheeting should be readily available, or kept on hand, to protect all slope areas from saturation by periods of heavy or prolonged rainfall. This measure is strongly recommended, beginning with the period of time prior to landscape planting. J4 REPAIRS J4.1 If slope failures occur, the Geotechnical Consultant should be contacted for a field review of site conditions and development of recommendations for evaluation and repair. J4.2 If slope failures occur as a result of exposure to periods of heavy rainfall, the failure area and currently unaffected areas should be covered with plastic sheeting to protect against additional saturation. J4.3 In the accompanying Standard Details, appropriate repair procedures are illustrated for superficial slope failures (i.e., occurring typically within the outer one foot to three feet of a slope face). Geotechnical Guidelines For Grading Projects Page 22 K. TRENCH BACKFILL Kl Utility trench backfill should, unless otherwise recommended, be compacted by mechanical means. Unless otherwise recommended, the degree of compaction should be a minimum of 90 percent of the laboratory maximum density. K2 As an alternative, granular material (sand equivalent greater than 30) may be thoroughly jetted in-place. Jetting should only be considered to apply to trenches no greater than two feet in width and four feet in depth. Following jetting operations, trench backfill should be thoroughly mechanically compacted and/or wheel rolled from the surface. K3 Backfill of exterior and interior trenches extending below a 1:1 projection from the outer edge of foundations should be mechanically compacted to a minimum of 90 percent of the laboratory maximum density. K4 Within slab areas, but outside the influence of foundations, trenches up to one foot wide and two feet deep may be backfilled with sand and consolidated by jetting, flooding or by mechanical means. If on-site materials are utilized, they should be wheel-rolled, tamped or otherwise compacted to a firm condition. For minor interior trenches, density testing may be deleted or spot testing may be elected if deemed necessary, based on review of backfill operations during construction. K5 If utility contractors indicate that it is undesirable to use compaction equipment in close proximity to a buried-conduit, the Contractor may elect the utilization of light weight mechanical compaction equipment and/or shading of the conduit with clean, granular material, which should be thoroughly jetted in-place above the conduit, prior to initiating mechanical compaction procedures. Other methods of utility trench compaction may also be appropriate, upon review by the Geotechnical Consultant at the time of-construction. K6 In cases where clean granular materials are proposed for use in lieu of native materials or where flooding or jetting is proposed, the procedures should be considered subject to review by the Geotechnical Consultant. K7 Clean granular backfill and/or bedding are not recommended in slope areas unless provisions are made for a drainage system to mitigate the potential build-up of seepage forces. Geotechnical Guidelines For Grading Projects Page 23 STATUS OF GRADING Prior to proceeding with any grading operation, the Geotechnical Consultant should be notified at least two working days in advance in order to schedule the necessary observation and testing services. LI Prior to any significant expansion or cut back in the grading operation, the Geotechnical Consultant should be provided with adequate notice (i.e., two days) in order to make appropriate adjustments in observation and testing services. L2 Following completion of grading operations and/or between phases of a grading operation, the Geotechnical Consultant should be provided with at least two working days notice in advance of commencement of additional grading operations. I I I i i i i 4 4 4 4 I 4 4 4 4 4 CANYON SUBDRAIN Proposed Grading .^ ~ Compacted Fill Bedrock =777=1 . Removal ofunsuitablematerial „ ' Bench: Vertical 4ft. Horizontal 6ft. min. Dozer Trench STBTl 31 F//S Drains along canyon walls as recommended by the geotechnical consultant. Install as - needed per buttress backdrain detail. Canyon Subdrain Geofabric Alternative etc. or open graded rock; 6 ft?/ft. Filter material - 9ft.3/ft.Nominal 2-3 Separation Backhoe Trench Geofabrlc Alternative Geofabric Minimum 15% open area; EOS = 40 -70 1ft. min. overlap. Filter Material 9ft.3/ft. Nominal 2-3" Notes:mm.mm. 1- Pipe be 4" min. diameter, 6" min. for runs of 500ft to 1000ft, 8" min. for runs of 1000ft. or greater. 2- Pipe should be schedule 40 PVC or similiar. Upstream ends should be capped. 3- Pipe should have 8 uniformly spaced 3/8" perforations per foot placed at 90°offset on underside of pipe. Final 20 foot of pipe should be nonperforated. 4- Filter material should be Calif. Class 2 Permable Material. 5- Appropriate gradiant should be provided for drainage; 2% minimum is recommended. 6- For the Geofabric Alternatives and gradients of 4% or greater, pipe maybe omitted from the upper 500ft. For runs of 500, 1000, and 1500ft or greater 4', 6', and 8'pipe, respectively, should be provided. STANDARD DETAIL NO.1 i r FILL OVER NATURAL SLOPE I I 1 1 1 1 1 i 4 J I J j JL HRecontour, slope to drain or provide paved drainage swales and down drains Backcut not steeper than 1:1 Bench: Vertical 4ft min. Horizontal 6ft min. •k 2ft. min. key depth at toe; tip key 1ft. nominal or 4% into slope FILL OVER CUT SLOPE Bench: Vertical 4ft min. Horizontal 6ft min. Backcut not steeper than 1:1 Notes: 1 - If overfilling and cutting back to grade is adopted, 15ft. min. fill width may be reduced to 12ft. min. In no case should the fill width be less than 1/2 the height of fill remaining. 2 - Backdrain as recommended by geotechnical consultant per buttress backdrain detail. STANDARD DETAIL NO.2 STABILIZATION FILL 1 ^ 4 Backcut 1:1 max. maintain 15ft. min. fill width i 15ft. Fill Slope 2:1 or flatter (1) 2 ft. min.3 ft. min. min. BUTTRESS FILL Fill Slope 2:1 ft or Hatter FT 0,E]—* r 3ft. min. '• ft. min. Horizontal 6 ft. min. Backdrain system if recommended by geotechnical consultant. maintain 15ft. min. widtr\ L Jrt /^_____i_w _^^\ mm.f-3*7 Bedding planes or other adverse geological condition. Bench: Vertical 4ft. min. Horizontal 6ft. min. Backdrain System per Standard Details I j ] j Notes: i] - If overfilling and cutting back to grade is adopted, 15ft. may be reduced to 12ft. In no case should the fill width be less than 1/2 the fill height remaining. 0 - A 3ft. blanket fill shall be provided above stabilization and buttress fills. The thickness may be greater as recommended by the geotechnical consultant. 0 - W = designed width of key. 1 - Dt = designed depth of key at toe ] - Dh = depth of key at heel; unless otherwise specified, Dh=Dt+ 1ft. STANDARD DETAIL NO. 1 I 1 1 1 j 4 J J STABILIZATION FILL *For H^18ft. additional upper drain may be omitted. H Horizontal spacing of outlets should be limited to about 100ft. 12.5 ft. nominal interval * 1 Blanket Fill, 3ft. min 1 See details below • 2 ft. nominal Conventional Backdrain Calif. Class 2 Permeable material 3ff/6. min. 2ft. min. 3ft. nominal Geofrabic Alternative 4in. min. Geofabric: Minimum 15% open area EOS = 40 - 70; 1ft. min. overlap.2ft. min. Notes: 1 - Pipe should be 4 inch diameter Schedule 40 PVC or similiar. 2 - Gradients should be 4% or greater. 3 - Cap all upstream ends 4 - Trenches for outlet pipes should be backfilled with compacted native soil. 5 • Backdrain pipe should have 8 uniformly spaced perforations per foot placed 90° offset on underside of pipe. Outlet pipe should be nonperforated. 6 - For the geofrabric alternative the backdrain pipe may be omitted provided at least 20 feet (i.e. 10ft each side of outlet) of perforated pipe is provided to lead into each outlet. 7 - At each outlet the geofabric should be appropriately overlapped (1ft.) at cuts in fabric or otherwise sealed or taped around the pipe. 4in. min. nominal Clean, open graded rock; pea gravel 3/8, 1/2, 3/4 or 1-inch; 3ft3/ft. min. STANDARD DETAIL NO. 4 I I I I I I I I I FUTURE CANYON FILL \/\ovi_Along Canyon——' Proposed Future Grade_ Current limit of engineered fill to Provide Drainage Unsuitable material (e.g. alluvium, topsoil, colluvium)Removal - Survey end ofsubdrain View of Canyon Sidewall Proposed Future Grade Future limit of engineered fill Future limit of engineered fill 1 Bedrock STANDARD DETAIL NO.5 iI i i 4 4 TRANSITION LOT OVER EXCAVATION Cut Lot per grading plan Removal, oftopsoil, colluvium, weathered bedrock 5ft. mm. Engineered Fill Finished Grade 3ft.\mm. Overexcavate and replace asengineered fill. Bench: Vertical 4ft. min.Horizontal 6ft. min. 6 inch. min. scarification in place and recompaction Cut-Fill Lot per grading plan. Engineered Fill per grading plan. ***** unsuitable materials „Overexcavate engineered fill. replace as Bench: Vertical 4ft. min. Horizontal 6ft. min. 6 inch. min. scarificationin Place and recompaction Notes: 1 - Topsoil, colluvium, weathered bedrock and otherwise unsuitable materials should be removed to firm natural ground as identified by the geotechnical consultant. 2 - The minimum depth of overexcavation should be considered subject to review by the geotechnical consultant. Steeper transitions may require deeper overexcavation. 3 - The lateral extent of overexcavation should be 5 feet minimum, but may include the entire lot as recommended by the geotechnical consultant 4 - The contractor should notify the geotechnical consultant in advance of achieving final grades (i.e. within 5 ft.) in order to evaluate overexcavation recommendations. Additional staking may be requested to aid in the evaluation of overexcavations. STANDARD DETAIL NO. I I I I I I I I •» 4 •» Finished Grade ROCK DISPOSAL 10ft. . min. I Fill Slope Stagger Locations of rock windrows ^ ) 20ft. nominal spacing 5ft. O Vertical Separation oBedrock or Firm Natural Ground«^<^A^^^^ Windrow Section F/// surface during grading —3ft. max.• 20ft. nominal spacing Windrow Profile Dozer V-dfah or fill thoroughly compacted to a smooth unyielding condition (e.g. by wheel rolling.) Place rock on 3 to 6 inches granular as recommended for flooding * Fill surface during grading clean grandular material (S.E> 30) should be thoroughly flooded to fill voids around rock. 1 „ Notes: ir\ 17v_ fedF/// IT Rnrt fin^l & /c y>«>"-\- ^^V^A^ XV N r/»Tt! " ( should be placed end to end. \ / c eshniiM nnt ha nftfsteri . v 1 - Following placement of rock, Hooding of granular material, and placement of compacted fill adjacent to windrow, each windrow should be thoroughly compacted from the surface. 2 - The contractor should provide to the geotechnical consultant plans prepared by survey documenting the location of buried rock. 3 - Disposal in streets may be subject to more restrictive requirements by the governing authorities. STANDARD DETAIL NO. \ \ \ 4 •I 00dLUQQDC<QIcn DC LLJ DC LJJ DL O CO DC O .art SOjs S-3 •«!§>S "3£ 3 1.1 So ^ to 2 •-•a o oo OK_110 &