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Home My WebLink AboutCT 16-02; OCEAN; PRELIMINARY GEOTECHNICAL INVESTIGATION, STATE STREET CONDOMINIUM PROJECT, 2501 STATE STREET CARLSBAD CALIFORNIA; 2016-03-30- -... - - - .. • .. --.. - -- 8AGS ADVANCED GEOTECHNICAL SOLUTIONS, INC. 9707 Waples Street, Suite 150 San Diego, California 92121 Telephone: (619) 867-0487 Soil Retention 2501 State Street Carlsbad, CA 92008 Attention: Mr. Jan Jansson March 30, 2016 P/W 1602-03 Report 1602-03-B-2 Subject: Preliminary Geotechnical Investigation, State Street Condominium Project, 2501 State Street, Carlsbad, California References: See Appendix A Gentlemen: In accordance with your request, presented herein are the results of Advanced Geotechnical Solutions, Inc.'s (AGS) preliminary geotechnical investigation for the proposed residential condominium project, located at 2501 State Street in Carlsbad, California. In accordance with our proposal, AGS conducted a preliminary geotechnical investigation of the proposed project site. In preparing this report AGS has utilized the 20-scale Preliminary Civil Site Plan prepared by Michael Baker International. Key geotechnical/geologic elements identified onsite that will affect the proposed development and which should be considered in the design and construction of the project include the following: •!• Unsuitable soil removals. •!• Excavation characteristics of soil and bedrock unit. •!• Undercut recommendations for building pads and improvements. •!• Grading recommendations. •!• Preliminary foundation design recommendations in anticipation of as-graded soil characteristics. The recommendations presented in this report are based on AGS' s recent subsurface and laboratory investigation and experience on similar projects in the vicinity of the project site. It is AGS's opinion, from a geotechnical standpoint, that the subject site is suitable for construction of the proposed multi- family residential development and associated improvements, provided the recommendations presented in this report are incorporated into the design, planning and construction. Included in this report are: 1) engineering characteristics of the onsite soils; 2) unsuitable soil removal recommendations; 3) grading recommendations; 4) foundation design recommendations; and 5) flatwork recommendations . Advanced Geotechnical Solutions, Inc., appreciates the opportunity to provide you with geotechnical consulting services and professional opinions. If you have questions regarding this report, please contact the undersigned at (619) 867-0487 . ORANGE AND L.A. COUNTIES (714) 786-5661 INLAND EMPIRE (619) 708-1649 RECEIVED APR O 4 2016 CITY OF CARLSBAD PLANNING DIVISION SAN DIEGO AND IMPERIAL COUNTIES (619) 867-0487 - ---- • - -- - • --.. ---• --------• ------ March 30, 2016 P/W 1602-03 Report No. 1602-03-B-2 Respectfully Submitted, Advanced Geotechnical Solutions, Inc. ~IT Staff Engineer Distribution: Attachments: (3) Addressee Figure l -Site Location Map ?~OZ PAUL J. DERISI, Vice President---._ CEG 2536, Reg. Exp. 5-31-17 Plate l -Geologic Map and Exploration Location Plan Appendix A -References Appendix B -Field Data Appendix C -Laboratory Data Appendix D -General Earthwork, Grading Guidelines & Details ADVANCED GEOTECHNICAL SOLUTIONS, INC. - -- ---- - - 111111 - -.. ----- March 30, 2016 P/W 1602-03 Page 1 Report No. 1602-03-B-2 1.0 1.1. 1.2. 1.3. INTRODUCTION Purpose and Background The purpose of this report is to provide geotechnical recommendations for the design and construction of the proposed condominium development at 2501 State Street in Carlsbad, CA. In preparing this report, AGS has conducted subsurface and laboratory investigations and reviewed the enclosed 20-scale Preliminary Civil Site Plan prepared by Michael Baker International, dated March 4, 2016. Pertinent subsurface information and laboratory data are included herein. Scope of Work The scope of our study consisted of the following: Review of available geologic and geotechnical literature. Mark-out for USA. Excavate, log, and sample three (3) soil borings with limited access tripod rig to maximum depth of 20 feet. Laboratory testing including moisture content and density, maximum density and optimum moisture content, undisturbed and remolded shear strength, consolidation, expansion index, and corrosivity. Provide remedial grading recommendations, including undercuts for building pads and underground improvements. Earthwork specifications. Estimation of shrink/swell parameters of the various onsite earth materials. Use of onsite soils as a foundation medium. Bearing and friction values. Preliminary foundation design. Preliminary pavement design. Design parameters for conventional retaining walls. Preparation of this report with appropriate exhibits. Site Location and Description The roughly rectangular site is located at 2501 State Street, Carlsbad, California. The site is bounded to the south by a multi-family residential development, to the north by a 3 story office building, to the west by a vacant lot and to the east by State Street. The site currently supports a one story commercial building and parking. Elevations onsite range from a high of 35MSL at the western property line to a low of 30 MSL at the northeast corner of the lot. The subject lot encompasses approximately 20,000 square feet. Previous land use onsite consisted of maintenance and storage facility supporting a water softening/filtration company. From information provided by your representatives it is our understanding that as part of the original development of the lot several ADVANCED GEOTECHNICAL SOLUTIONS, INC. I I I I I N ~ SOURCE MAP-TOPOGRAPHIC MAP OF THE SAN LUTS REY 7.5 MINUTE QUADRANGLE, SAN DIEGO COUNTY, CALIFORNIA SITE LOCATION MAP 2501 STATE STREET CARLSBAD, CALIFORNIA P/W 1602-03 FIGURE 1 -.. - - .. -- - - ,..., - -----• ------ March 30, 2016 P/W 1602-03 Page 2 Report No. 1602-03-B-2 1.4. 2.0 reinforced concrete slabs were constructed at the rear (Westside) of the lot. These slabs are estimated to range from 6 to 18 inches thick. Report Limitations The conclusions and recommendations in this report are based on field and laboratory data developed during this investigation, a review of readily available geologic and geotechnical information, and the preliminary civil site plan prepared by Michael Baker International. The materials immediately adjacent to, or beneath those observed in the exploratory excavations may have different characteristics and no representations are made as to the quality or extent of materials not observed. The recommendations presented herein are specific to the development plans reflected on the current civil site plan. Modifications to that design or development plans could necessitate revisions to these recommendations. PROPOSED DEVELOPMENT Based upon our discussions, it is our understanding that the existing structures and improvements will be razed. The site will then be graded to support a four story high multifamily residential "Podium" type structure along with associated driveways and improvements. It is anticipated that the proposed structure will be constructed at or near the existing elevations onsite. At this time structural plans are not available. Based upon our conversations it is anticipated that the structure will be supported by conventional spread and continuous footings. 3.0 3.1. 3.2. FIELD AND LABO RA TORY INVESTIGATION Field Investigation In February 2015, AGS performed a field investigation to aid in the determination of the engineering properties of the onsite soils, and evaluate whether any adverse geotechnical conditions were present. The subsurface investigation consisted of the logging and sampling of three (3) 6-inch diameter solid stem auger soil borings with a limited access tripod rig (BA-1 thru BA-3). The approximate locations of the borings are depicted on Plate 1. Logs of these borings are presented in Appendix B. During our recent subsurface investigation two of these slabs were encountered and halted advancement of our drill rig at depths as shallow as 12-18 inches below existing grade. Laboratory Investigation Bulk and "undisturbed" ring samples were obtained during the subsurface investigation for use in our laboratory testing. Selected samples were used to determine in-situ moisture content and density, maximum dry density and optimum moisture content, "undisturbed" and remolded shear strengths, expansion potential, consolidation, and corrosivity. Laboratory data generated from these borings are presented in Appendix C. ADVANCED GEOTECHNICAL SOLUTIONS, INC. ... --... • -• ... ---- 111111 -... - .... ... 1/111 ... -.. • ---• -• March 30, 2016 P/W 1602-03 Page 3 Report No. 1602-03-B-2 4.0 4.1. 4.2. 4.3. ENGINEERING GEOLOGY Regional Geologic and Geomorphic Setting The subject site is situated within the Peninsular Ranges Geomorphic Province. The Peninsular Ranges province occupies the southwestern portion of California and extends southward to the southern tip of Baja California. In general, the province consists of young, steeply sloped, northwest trending mountain ranges underlain by metamorphosed Late Jurassic to Early Cretaceous-aged extrusive volcanic rock and Cretaceous-aged igneous plutonic rock of the Peninsular Ranges Batholith. The westernmost portion of the province, where the subject site is located, is predominantly underlain by younger marine and non-marine sedimentary rocks. The Peninsular Ranges' dominant structural feature is northwest-southeast trending crustal blocks bounded by active faults of the San Andreas transform system. Subsurface Conditions Based on our recent subsurface excavations and review of geologic maps and literature, the area of proposed development is covered with a veneer of undocumented fill which is underlain by Old Paralic deposits. The following is a brief summary of the encountered geologic units within the proposed development area. Approximate locations of the borings are shown on Plate 1. Logs are presented in Appendix B. 4.2.1. Undocumented Artificial Fill (Map Symbol afu) Undocumented artificial fill was encountered in all three borings. As encountered, these materials generally consist of brown to grayish brown, silty to clayey sand and sandy clay in a moist to very moist and loose to medium dense/firm to stiff condition. These materials overlay old paralic deposits and were found to range from 8 to 10 feet in thickness. Locally deeper undocumented artificial fill may exist at the site. The reinforced concrete slab encountered below the existing asphalt pavement at boring B-3 extended to a depth of 12- inches . 4.2.2. Old Paralic Deposits, Unit 6 (Map Symbol Qop6) Old paralic deposits were encountered in all three borings beneath the undocumented fill soils. As encountered, these materials generally consist of brownish gray fine to medium grained sand in a slightly moist and medium dense to dense condition and light greenish gray and light yellowish brown, slightly silty to clayey sand in a moist and very dense condition . Groundwater Groundwater was not encountered in any of the borings during our recent field investigation. No groundwater condition is known to exist at the site that would affect the proposed site development. Onsite grades range from elevation 31 to 34 MSL. It is anticipated that final grades for the structure will generally be similar to the existing grades. Considering the proximity of the he northerly adjacent lagoon (approximately 200 lineal feet), although unlikely, groundwater could be encountered as shallow as l lMSL (20 to 25 feet below pad grade. Further, it should be noted that ADVANCED GEOTECHNICAL SOLUTIONS, INC. ... - .. , ... --.. ----,. -... - -... • • .. • -- - March 30, 2016 P/W 1602-03 Page4 Report No. 1602-03-B-2 4.4. localized perched groundwater could develop closer to finished grade, due to fluctuations in precipitation, irrigation practices, tides, or factors not evident at the time of our field explorations . Faulting and Seismicity The site is located in the tectonically active Southern California area, and will therefore likely experience shaking effects from earthquakes. The type and severity of seismic hazards affecting the site are to a large degree dependent upon the distance to the causative fault, the intensity of the seismic event, and the underlying soil characteristics. The seismic hazard may be primary, such as surface rupture and/or ground shaking, or secondary, such as liquefaction or dynamic settlement. The following is a site-specific discussion of ground motion parameters, earthquake-induced landslide hazards, settlement, and liquefaction. The purpose of this analysis is to identify potential seismic hazards and propose mitigations, if necessary, to reduce the hazard to an acceptable level of risk. The following seismic hazards discussion is guided by the California Building Code (2013), CDMG (2008), and Martin and Lew (1998). 4.4.1. Surface Fault Rupture No known active faults have been mapped at or near the subject site. The nearest known active surface fault is the Oceanside section of the Newport-Inglewood-Rose Canyon fault zone which is approximately 5 miles west of the subject site. Accordingly, the potential for fault surface rupture on the subject site is considered to be "very low to remote". This conclusion is based on literature and map review. 4.4.2. Seismicity As noted, the site is within the tectonically active southern California area, and is approximately 5 miles from an active fault, the Oceanside section of the Newport- Inglewood-Rose Canyon fault zone. The potential exists for strong ground motion that may affect future improvements. At this point in time, non-critical structures ( commercial, residential, and industrial) are usually designed according to the California Building Code (2013) and that of the controlling local agency. However, liquefaction/seismic slope stability analyses, critical structures, water tanks and unusual structural designs will likely require site specific ground motion input. 4.4.3. Liquefaction Liquefaction is the phenomenon in which the buildup of excess pore pressures, in saturated granular soils due to seismic agitation, results in a temporary "quick" or "liquefied" condition. Loose lenses/layers of sandy soils may be subject to liquefaction when a large, prolonged, seismic event affects the site. Once the excess pore water pressure dissipates, the liquefied zones/lenses will likely consolidate causing settlement. Post liquefaction effects at a site can manifest in several ways, and may include: ground deformations, loss of bearing strength, lateral spreading, flow failure, and dynamic settlement. ADVANCED GEOTECHNICAL SOLUTIONS, INC. -----.. --- • -- .. --- - - • -• ---• ---- March 30, 2016 P/W 1602-03 Page 5 Report No. 1602-03-B-2 4.5. Due to age and dense nature of the Old Paralic Deposits, and the remedial grading as proposed herein, the potential for seismically induced liquefaction is considered "very low" to "low" . 4.4.4. Dynamic Settlement Dynamic settlement occurs in response to an earthquake event in loose sandy earth materials. This potential of dynamic settlement at the subject site is considered to be remote due to the presence of well consolidated old paralic deposits and the absence of loose, sandy soils after the remedial grading recommended herein is completed. 4.4.5. Seismically Induced Landsliding Evidence of landsliding at the site was not observed during our field observations, nor are there any geomorphic features indicative of landsliding noted in our review of published geologic maps. Further, given the relatively flat nature of the site, the likelihood for seismically induced landsliding is considered to be remote. 4.4.6. Tsunamis Our review of the 2009 Tsunami Inundation Map for Emergency Planning, San Luis Rey Quadrangle, prepared by CalEMA, indicates the project site is not located within the tsunami inundation line. This line represents the maximum considered tsunami run-up from a number of local and distant tsunami sources. The suite of tsunami source events selected for modeling represents possible but extreme and rare events. As such, no information about the probability of any tsunami affecting any area within a specific period of time is provided. In addition, the map does not represent inundation from a single scenario event. Rather, it was created by combining inundation results for an ensemble of source events affecting a region. Recent studies indicate that significant run-up heights in the San Diego area due to distant tsunami source events are highly unlikely in consideration of the offshore topography and presence of islands along the southern California borderlands. In addition, the protected shoreline in the project vicinity will further inhibit significant run-up heights during a tsunami event. Accordingly, it is our opinion that tsunamis are not a significant risk at the project site . Non-seismic Geologic Hazards 4.5.1. Mass Wasting No evidence of mass wasting was observed onsite nor was any noted on the reviewed maps. 4.5.2. Flooding According to available FEMA maps, the site is not in a FEMA identified flood hazard area. ADVANCED GEOTECHNICAL SOLUTIONS, INC. - - --- - - - .. • .. ------- March 30, 2016 P/W 1602-03 Page 6 Report No. 1602-03-B-2 5.0 4.5.3. Subsidence/Ground Fissuring Due to the presence of the dense underlying materials, the potential for subsidence and ground fissuring due to settlement is unlikely. ENGINEERING ANALYSIS Presented herein is a general discussion of the geotechnical properties of the various soil types and earth materials summarized from our site-specific analyses of the project and the referenced reports. 5.1. Material Properties 5.1.1. Excavation Characteristics The onsite soils within the anticipated remedial grading depths should be readily excavatable with conventional grading equipment. Excavations in the north-central portion of the site within the "drivable grass" area will encounter the lined retention basin below ground surface. During our investigation, this basin was observed to contain several feet of water. Accordingly, the water collected within this basin should be removed prior to construction, or special measures may be required to efficiently excavate the saturated soil/gravel in the basin. 5.1.2. Compressibility Onsite materials that are significantly compressible include undocumented fill and highly weathered Old Paralic deposits. These materials will require complete removal prior to placement of fill, and where exposed at design grade. If removals are impossible due to property line restraints these improvements should be designed for the total and differential settlement potentials as outlined in Table 5.1.2. Recommended removal depths are presented in Section 6.1, and earthwork adjustment estimates are presented in Section 5.1.5. TABLES.1.2 SETTLEMENT POTENTIAL Total (inches) Differential (inches in 20 feet) 3/4 3/8 5.1.3. Expansion Potential Our testing indicates that the upper onsite soils tested possess an expansion index (EI) of 103 which classifies these soils as having a "High" expansion potential (CBC 2013) . Generally, the upper onsite soils consist of clayey sand to sandy clay. Based upon our familiarity with the general area it is anticipated that the expansion potential of the onsite materials will vary from "Medium" to "High". Final determination of expansion potential for foundation design purposes should be based on testing of the as-graded soil conditions. ADVANCED GEOTECHNICAL SOLUTIONS, INC. - 1111111 -- - - - ---.. • ----.. ... -----.. - ---- March 30, 2016 P/W 1602-03 Page 7 Report No. 1602-03-B-2 6.0 5.1.4. Shear Strength Characteristics Shear strength testing was conducted on "undisturbed" and "remolded" bulk samples of the onsite soils. Based upon the results of shear testing and our previous experience in the general area with similar soils, the following are assumed shear strengths for the onsite soils. TABLES.1.4 SHEAR STRENGTH Material Cohesion Friction Angle (ps.f) (de~rees) Existing Compacted Fill 500 22 Select Imported Granular Fill 150 33 Old Paralic Deposits 150 32 5.1.5. Earthwork Adjustments The following table 5.1.5 presents bulk/shrink values of the various onsite soils for use in estimating earthwork grading quantities. TABLES.LS SHRINK/SWELL PARAMETERS Undocumented Fill Shrink 6-10% Old Paralic Deposits Bulk2-5% These values may be used in an effort to balance the earthwork quantities. As is the case with every project, contingencies should be made to adjust the earthwork balance when grading is in progress and actual conditions are better defined. 5.1.6. Chemical/Resistivity Analyses Testing of onsite soil samples indicates the soils exhibited "negligible" sulfate exposure when classified in accordance with ACI 318-11 Table 4.2.1 (per 2013 CBC). Accordingly, the use of sulfate resistant concrete is not anticipated . Preliminary resistivity and chloride testing indicates that onsite soils are "moderately" corrosive to metals. In the past on similar projects, corrosion protection typically consisted of non-metallic piping for water lines to and below the slabs or by installing above slab plumbing. Consultation with a corrosion engineer is recommended. Consultation with a corrosion engineer is recommended. Final design should be based upon representative sampling of the as-graded soils. GEOTECHNICAL ENGINEERING Development of the subject property as proposed is considered feasible, from a geotechnical standpoint, provided that the conclusions and recommendations presented herein are incorporated into the design and construction of the project. Presented below are specific issues identified by this study or previous studies as ADVANCED GEOTECHNICAL SOLUTIONS, INC. ------------------------------------------------- --... • ... -... , .... - - -- ... .,,, ... -.. ... -.. .. -- March 30, 2016 P/W 1602-03 Page 8 Report No. 1602-03-B-2 possibly impacting site development. Recommendations to mitigate these issues are presented in the text of this report . 6.1. Site Preparation and Removals Grading should be accomplished under the observation and testing of the project soils engineer and engineering geologist or their authorized representative in accordance with the recommendations contained herein, the current grading ordinance of the City of Carlsbad, and AGS's Earthwork Specifications (Appendix D). Undocumented fill and highly weathered Old Paralic Deposits should be removed in structural areas planned to receive fill or where exposed at final grade. Removals should expose competent formational materials and be observed and mapped by the engineering geologist prior to fill placement. It is anticipated that the upper eight to ten feet of the onsite soils will require removal and recompaction for the support of settlement sensitive structures. Localized areas may require deeper removals. The resulting undercuts should be replaced with engineered fill. The extent of removals can best be determined in the field during grading when observation and evaluation can be performed by the soil engineer and/or engineering geologist. In general, soils removed during remedial grading will be suitable for reuse in compacted fills, provided they are properly moisture conditioned and do not contain deleterious materials. 6.1.1. Stripping and Deleterious Material Removal Existing vegetation, trash, debris from site demolition activities, and other deleterious materials should be removed and wasted from the site prior to removal of unsuitable soils and placement of compacted fill. 6.1.2. Undocumented Fill (Map Symbol afu) Undocumented fill soil will require complete removal and recompaction to project specifications where encountered below proposed settlement sensitive structures or improvements. Estimated depths of removal are from eight to ten feet. Locally deeper areas may be encountered. Based on our field exploration, it is anticipated that undocumented fills onsite will be encountered throughout the site. Where existing concrete slabs are encountered these slabs can be crushed and used as fill materials provided that all rebar is removed and the material is reduced to a manageable size (6 to 12 inches). 6.1.3. Old Paralic Deposits (Map Symbol Qop) It is anticipated that the existing Old Paralic Deposits are generally considered to be suitable for support of settlement sensitive structures. There is typically a thin veneer of weathered materials at the upper boundary of the Old Paralic Deposits. Weathered formational materials should be removed prior to fill placement in structural fill areas. Final determination will be made in the field during grading . 6.1.4. Removals Along Grading Limits and Property Lines Removals of unsuitable soils will be required prior to fill placement along the grading limit. As currently depicted on the Civil Site Plan, the proposed building footprint extends to ADVANCED GEOTECHNICAL SOLUTIONS, INC. ,_ -... ----- - ---• -- - March 30, 2016 P/W 1602-03 Page9 Report No. 1602-03-B-2 within a few feet of the property line. A 1: 1 projection, from the edge of the building footprint, down to suitable materials and back up at 1: 1 to existing grade should be established, where possible. Where removals are not possible due to grading limits, property line or easement restrictions, removals should be initiated at the grading boundary (property line, easement, grading limit or outside the improvement) at a 1:1 ratio inward to competent materials. Along theses edges specialized grading techniques may be required to conduct the necessary removals for support of the proposed structures and to facilitate foundation construction. These "specialized grading" techniques could range from temporary shoring to excavation and recompaction with trenching techniques. If removals cannot be conducted deepened foundations may be required. Where this reduced removal criteria is implemented, special maintenance zones may be necessary. 6.2. Excavations and Temporary Backcut Stability 6.3 . During grading operations, temporary backcuts may be required to accomplish remedial grading. Backcuts in undocumented fill and bedrock areas should be made no steeper than 1: 1. Construction backcuts and trenches shall be excavated as per CAL/OSHA requirements. The Old Paralic Deposits can be considered a Type "A" Soil, and the fill soils can be considered a Type "B" Soil. Where property limits make 1: 1 backcuts impossible, shoring may be required. In consideration of the inherent instability created by temporary construction backcuts, it is imperative that grading schedules are coordinated to minimize the unsupported exposure time of these excavations. Once started, these excavations and subsequent fill operations should be maintained to completion without intervening delays imposed by avoidable circumstances. In cases where five-day workweeks comprise a normal schedule, grading should be planned to avoid exposing at-grade or near-grade excavations through a non-work weekend. Where improvements may be affected by temporary instability, either on or offsite, further restrictions such as slot cutting, extending work days, implementing weekend schedules, and/or other requirements considered critical to serving specific circumstances may be imposed. 6.2.1. Shoring Parameters Soil parameters for use in shoring design, if needed, are as follows: Unit Weight of Soil= 125 lbs./cu.ft. <p = 22 degrees C = 300 lbs./sq.ft. External loads that may affect the shoring include: 1) groundwater; 2) adjacent underground conduits and utilities; 3) surface and subsurface structures; 4) loading and vibration from traffic and construction equipment; and 5) loads that may be applied by construction materials and excavated soil. Slope Stability According to the preliminary civil site plan, no cut slopes or fill slopes are anticipated onsite. ADVANCED GEOTECHNICAL SOLUTIONS, INC. - ,.,, ... - ... .... -.. -,. --- March 30, 2016 P/W 1602-03 Page 10 Report No. 1602-03-B-2 6.4. Construction Staking and Survey Removal bottoms, keyways, subdrains and backdrains should be surveyed by the civil engineer after approval by the geotechnical engineer/engineering geologist and prior to the placement of fill. Toe stakes should be provided by the civil engineer in order to verify required key dimensions and locations. 6.5. Earthwork Considerations 6.6. 6.5.1. Compaction Standards Fill and processed natural ground shall be compacted to a minimum relative compaction of 90 percent as determined by ASTM Test Method: D 1557. Care should be taken that the ultimate grade be considered when determining the compaction requirements for disposal fill areas. Compaction shall be achieved at slightly above the optimum moisture content, and as generally discussed in the attached Earthwork Specifications (Appendix D). 6.5.2. Documentation of Removals and Drains Removal bottoms fill keys, backcuts, backdrains and their outlets should be observed and approved by the engineering geologist and/or geotechnical engineer and documented by the civil engineer prior to fill placement. 6.5.3. Treatment of Removal Bottoms At the completion of removals, the exposed bottom should be scarified to a practical depth, moisture conditioned to above optimum conditions, and compacted in-place to the standards set forth in this report. 6.5.4. Fill Placement After removals, scarification, and compaction of in-place materials are completed, additional fill may be placed. Fill should be placed in thin lifts [eight-(8) inch bulk], moisture conditioned to slightly above the optimum moisture content, mixed, compacted, and tested as grading progresses until final grades are attained. 6.5.5. Benching Where the natural slope is steeper than 5-horizontal to I-vertical, and where designed by the project geotechnical engineer or geologist, compacted fill material should be keyed and benched into competent bedrock or firm natural soil. 6.5.6. Mixing In order to provide thorough moisture conditioning and proper compaction, processing (mixing) of materials is necessary. Mixing should be accomplished prior to, and as part of the compaction of each fill lift. Haul Roads Haul roads, ramp fills, and tailing areas should be removed prior to placement of fill. ADVANCED GEOTECHNICAL SOLUTIONS, INC. - - .. -- - - - - ----... --• -- March 30, 2016 P/W 1602-03 Page 11 Report No. 1602-03-B-2 6.7. 7.0 Import Materials Should import materials be required to achieve design site grades, these materials should have similar engineering characteristics as the onsite soils and should be approved by the soil engineer at the source prior to importation to the site. CONCLUSIONS AND RECOMMENDATIONS Construction of the proposed multi-family residential structure and associated improvements is considered feasible, from a geotechnical standpoint, provided that the conclusions and recommendations presented herein are incorporated into the design and construction of the project. Presented below are specific issues identified by this study as possibly affecting site development. Recommendations to mitigate these issues are presented in the text of this report. 7.1. Preliminary Design Recommendations It is our understanding that the proposed foundations will consist of conventionally reinforced spread and continuous footings. From a geotechnical perspective these proposed improvements are feasible provided that the following recommendations are incorporated into the design and construction. 7.1.1. Foundation Design Criteria The multi-family residential structures can be supported by conventional shallow foundation systems. The expansion potential of the underlying soils is anticipated to range from "medium" to "high" The following preliminary values may be used in the foundation design. Allowable Bearing: Lateral Bearing: Sliding Coefficient: 3000 lbs./sq.ft. (Assuming 18-inch embedment, 500 lbs./sq.ft increase for each additional 6-inches of embedment to a maximum of 4000 lbs./sq.ft) 250 lbs./sq.ft. at a depth of 12 inches plus 125 lbs./sq.ft. for each additional 12 inches embedment to a maximum of 3000 lbs./sq.ft. 0.30 The above values may be increased as allowed by Code to resist transient loads such as wind or seismic. Building Code and structural design considerations may govern. Depth and reinforcement requirements should be evaluated by the Structural Engineer. 7.1.2. Conventional Foundation Design Recommendations Based upon the onsite soil conditions and information supplied by the CBC-2013, conventional foundation systems should be designed in accordance with Section 7 .1.1 and the following recommendations: ~ Three-story -Interior and exterior footings should be a minimum of 18 inches wide and extend to a depth of at least 24 inches below lowest adjacent grade. Footing reinforcement should minimally consist of four No. 4 reinforcing bars, two top and two bottom or two No. 5 reinforcing bars, one top and one bottom ADVANCED GEOTECHNICAL SOLUTIONS, INC. - • ... -- ---- -- -.. -------- March 30, 2016 P/W 1602-03 Page 12 Report No. 1602-03-B-2 );;.,, Slab -Conventional, slab-on-grade floors or parking garage slabs, underlain by "low to medium" expansive compacted fill, should be five or more inches thick and be reinforced with No. 3 or larger reinforcing bars spaced 15 inches on center each way. For "high" expansive compacted fill, should be five or more inches thick and be reinforced with No. 3 or larger reinforcing bars spaced 12 inches on center each way. The slab reinforcement and expansion joint spacing should be designed by the Structural Engineer. );;.,, Embedment -Footings adjacent to slopes should be embedded such that a least seven feet are provided horizontally from edge of the footing to the face of the slope. );;.,, Isolated Spread Footings -Isolated spread footings should be embedded a minimum of 24 inches below lowest adjacent finish grade and should at least 24 inches wide. A grade beam should also be constructed for interior and exterior spread footings and should be tied into the structure in two orthogonal directions footing dimensions and reinforcement should be similar to the aforementioned continuous footing recommendations. Final depth, width and reinforcement should be determined by the structural engineer. );;.,, Presaturation -Prior to concrete placement the subgrade soils should be moisture conditioned to the following: Low Expansion Potential -Minimum of optimum moisture prior to concrete placement. Medium Expansion Potential -Minimum of 120% of optimum moisture at least 24 hours prior to concrete placement. High to Very High Expansion Potential -Minimum of 130% of optimum moisture at least 48 hours prior to concrete placement. 7 .1.3. Seismic Design Parameters The following seismic design parameters are presented to be code compliant to the California Building Code (2013). The subject site has been identified to be Site Class "D" in accordance with CBC, 2013, Section 1613.3.2 and ASCE 7, Chapter 20. The site is located at Latitude 33.1648° N and Longitude 117.3537° W. Utilizing this information, the United States Geological Survey (USGS) web tool (http://earthquake.usgs.gov/designmaps/us/) and ASCE 7 criterion, the mapped seismic acceleration parameters Ss, for 0.2 seconds and S1, for 1.0 second period (CBC, 2013, 1613.3.1) for Risk-Targeted Maximum Considered Earthquake (MCER) can be determined. The mapped acceleration parameters are provided for Site Class "B". Adjustments for other Site Classes are made, as needed, by utilizing Site Coefficients Fa and Fv for determination of MCER spectral response acceleration parameters SMs for short periods and SM1 for 1.0 second period (CBC, 2013 1613.3.3). Five-percent damped design spectral response acceleration parameters SDs for short periods and SD 1 for 1.0 second period can be determined from the equations in CBC, 2013, Section 1613.3.4. ADVANCED GEOTECHNICAL SOLUTIONS, INC. --,., ""' • -.. ""' • -- • --.. -- - - ... • • • • -• -• March 30, 2016 P/W 1602-03 TABLE 7.1.3 Seismic Design Criteria Mapped Spectral Acceleration (0.2 sec Period), Ss Mapped Spectral Acceleration (1.0 sec Period), S1 Site Coefficient, Fa Site Coefficient, Fv MCE Spectral Response Acceleration (0.2 sec Period), SMs MCE Spectral Response Acceleration (1.0 sec Period), SM1 Page 13 Report No. 1602-03-B-2 1.165g 0.447g 1.034 1.553 1.205g 0.694g Design Spectral Response Acceleration (0.2 sec Period), SDs 0.803g Design Spectral Response Acceleration (1.0 sec Period), SD1 0.463g Utilizing a probabilistic approach, the CBC recommends that structural design be based on the peak horizontal ground acceleration (PGA) having of 2 percent probability of exceedance in 50 years (approximate return period of 2,475 years) which is defined as the Maximum Considered Earthquake (MCE). Using the United States Geological Survey (USGS) web-based ground motion calculator, the site class modified PGAM (FPGA *PGA) was determined to be 0.480g. This value does not include near-source factors that may be applicable to the design of structures on site. 7.1.4. Under Slab A moisture and vapor retarding system should be placed below the slabs-on-grade in portions of the structure considered to be moisture sensitive. The retarder should be of suitable composition, thickness, strength and low permeance to effectively prevent the migration of water and reduce the transmission of water vapor to acceptable levels. Historically, a IO-mil plastic membrane, such as Visqueen, placed between one to four inches of clean sand, has been used for this purpose. More recently Stego® Wrap or similar underlayments have been used to lower permeance to effectively prevent the migration of water and reduce the transmission of water vapor to acceptable levels. The use of this system or other systems, materials or techniques can be considered, at the discretion of the designer, provided the system reduces the vapor transmission rates to acceptable levels. 7.1.5. Deepened Footings and Structural Setbacks It is generally recognized that improvements constructed in proximity to natural slopes or properly constructed, manufactured slopes can, over a period of time, be affected by natural processes including gravity forces, weathering of surficial soils and long-term (secondary) settlement. Most building codes, including the California Building Code (CBC), require that structures be set back or footings deepened, where subject to the influence of these natural processes . For the subject site, where foundations for residential structures are to exist in proximity to slopes, the footings should be embedded to satisfy the requirements presented in Figure 2. ADVANCED GEOTECHNICAL SOLUTIONS, INC. - - --... -.. ,. .. -.. • ,. • .. -.. --- --------- --- March 30, 2016 P/W 1602-03 FACE OF STRUCTURE Hl2. BUT NEED NOT EXCEED 15 FT. MAX. FIGURE2 Page 14 Report No. 1602-03-B-2 FACE OF FOOTING H/3 BUT NEED NOT EXCEED 40 FT. MAX. H j 7.1.6. Concrete Design Preliminary testing indicates onsite soils exhibit a "negligible" sulfate exposure when classified in accordance with ACI 318-11 Table 4.2.1 (per 2013 CBC). However, some fertilizers have been known to leach sulfates into soils otherwise containing "negligible" sulfate concentrations and increase the sulfate concentrations to potentially detrimental levels. It is incumbent upon the owner to determine whether additional protective measures are warranted to mitigate the potential for increased sulfate concentrations to onsite soils as a result of the future homeowner' s actions . 7.1.7. Retaining Walls The following earth pressures are recommended for the design of conventional retaining walls onsite: Static Case (Non Select compacted fill: 125pcf and phi=22°) Rankine Level Backfill Coefficients Coefficient of Active Pressure: Ka = 0.45 Coefficient of Passive Pressure: Kp = 2.20 Coefficient of at Rest Pressure: Ka = 0.63 Equivalent Fluid Pressure (psf/lin.ft.) 57 275 78 Static Case (Select compacted fill: 125pcf and phi=32°) Rankine Level Backfill Coefficients Coefficient of Active Pressure: Ka = 0.31 Coefficient of Passive Pressure: KP= 3.25 Coefficient of at Rest Pressure: Ka= 0.47 Equivalent Fluid Pressure (psf/lin.ft.) 38 407 59 ADVANCED GEOTECHNICAL SOLUTIONS, INC. ---- ... ---- ---- -.... --.. ... .. • -• ------ - March 30, 2016 P/W 1602-03 Seismic Case Page 15 Report No. 1602-03-B-2 In addition to the above static pressures, unrestrained retaining walls located should be designed to resist seismic loading as required by the 2013 CBC. The seismic load can be modeled as a thrust load applied at a point 0.6H above the base of the wall, where H is equal to the height of the wall. This seismic load (in pounds per lineal foot of wall) is represented by the following equation: Where: Pe = ¾ *y*H2 *ki, Pe = Seismic thrust load H = Height of the wall (feet) y = soil density = 125 pounds per cubic foot (pct) kh = seismic pseudostatic coefficient = 0.5 * peak horizontal ground acceleration / g The peak horizontal ground accelerations are provided in Section 7.1.3. Walls should be designed to resist the combined effects of static pressures and the above seismic thrust load. The foundations for retaining walls may bear on properly compacted fill. A bearing value of 3,000 psf may be used for design of retaining walls. Retaining wall footings should be designed to resist the lateral forces by passive soil resistance and/or base friction as recommended for foundation lateral resistance. To relieve the potential for hydrostatic pressure wall backfill should consist of a free draining backfill (sand equivalent "SE" >20) and a heel drain should be constructed (see Figure 4). The heel drain should be place at the heel of the wall and should consist of a 4-inch diameter perforated pipe (SDR35 or SCHD 40) surrounded by 4 cubic feet of crushed rock (3/4-inch) per lineal foot, wrapped in filter fabric (Mirafi® 140N or equivalent). Proper drainage devices should be installed along the top of the wall backfill, which should be properly sloped to prevent surface water ponding adjacent to the wall. In addition to the wall drainage system, for building perimeter walls extending below the finished grade, the wall should be waterproofed and/or damp-proofed to effectively seal the wall from moisture infiltration through the wall section to the interior wall face. The wall should be backfilled with granular soils placed in loose lifts no greater than 8- inches thick, at or near optimum moisture content, and mechanically compacted to a minimum 90 percent relative compaction as determined by ASTM Test Method D1557. Flooding or jetting of backfill materials generally do not result in the required degree and uniformity of compaction and, therefore, is not recommended. The soils engineer or his representative should observe the retaining wall footings, backdrain installation and be present during placement of the wall backfill to confirm that the walls are properly backfilled and compacted. ADVANCED GEOTECHNICAL SOLUTIONS, INC. I I I I I I I March 30, 2016 P/W 1602-03 Page 16 Report No. 1602-03-B-2 H WATERPROOFING MEMBRANE (CPTIONAL) . . ~ ,. I .. ~ FIGURE3 min . ----~ SELECT I BACKFILL I (El<.20 & I SE>20) \ H/2 J mn. I \ i ,J' NATIVE 8ACKFIU. (El<SO) I 1:1 (H:V) OR FLATTER litllfS:. (1) l2&1l:t. 4-INCH PERFORA~OABS OR PVC PPE OR APPROVED EOU\11\1.Ellr SIJBSTIT\ITE P\ACEO PERFORATIONS OOWNAND SIJRROUl«lEO BY A MNMUMOF 1 CUBIC FEETOF3/41NCH ROCKORAl'PROIIED EOU""LENT SIJBSTITUTEANOWAAPPEOINt.lRAA 140FL-FAIIRCORAPPRO\IED EOUl\1111.ENT SIJBSllTurE 7.2. Utility Trench Excavation 7.3. 7.4. All utility trenches should be shored or laid back in accordance with applicable OSHA standards. Excavations in bedrock areas should be made in consideration of underlying geologic structure. AGS should be consulted on these issues during construction. Utility Trench Backfill Mainline and lateral utility trench backfill should be compacted to at least 90 percent of maximum dry density as determined by ASTM D 1557. Onsite soils will not be suitable for use as bedding material but will be suitable for use in backfill, provided oversized materials are removed. No surcharge loads should be imposed above excavations. This includes spoil piles, lumber, concrete trucks or other construction materials and equipment. Drainage above excavations should be directed away from the banks. Care should be taken to avoid saturation of the soils. Compaction should be accomplished by mechanical means. Jetting of native soils will not be acceptable. Exterior Slabs and Walkways 7.4.1. Subgrade Compaction The subgrade below exterior slabs, sidewalks, driveways, patios, etc. should be compacted to a minimum of 90 percent relative compaction as determined by ASTM D 1557. ADVANCED GEOTECHNICAL SOLUTIONS, INC. .. ---- -----.. • .. - --- - -.. ... -.. • ------ March 30, 2016 P/W 1602-03 Page 17 Report No. 1602-03-B-2 7.5. 7.4.2. Subgrade Moisture The subgrade below exterior slabs, sidewalks, driveways, patios, etc. should be moisture conditioned to a minimum of 110 (low expansive soils), 120 (medium expansive soils), 130 (high expansive soils) percent of optimum moisture content prior to concrete placement, dependent upon the expansion potential of the subgrade soils. 7.4.3. Slab Thickness Concrete flatwork and driveways should be designed utilizing four-inch minimum thickness. 7.4.4. Control Joints Weakened plane joints should be installed on walkways at intervals of approximately eight to ten feet. Exterior slabs should be designed to withstand shrinkage of the concrete . 7.4.5. Flatwork Reinforcement Consideration should be given to reinforcing any exterior flatwork. 7.4.6. Thickened Edge Consideration should be given to construct a thickened edge (scoop footing) at the perimeter of slabs and walkways adjacent to landscape areas to minimize moisture variation below these improvements. The thickened edge (scoop footing) should extend approximately eight inches below concrete slabs and should be a minimum of six inches wide. Plan Review Once approved grading and foundation design plans become available, they should be reviewed by AGS to verify that the design recommendations presented are consistent with the proposed construction. 7 .6. Geotechnical Review As is the case in any grading project, multiple working hypotheses are established utilizing the available data, and the most probable model is used for the analysis. Information collected during the grading and construction operations is intended to evaluate the hypotheses, and some of the assumptions summarized herein may need to be changed as more information becomes available. Some modification of the grading and construction recommendations may become necessary, should the conditions encountered in the field differ significantly than those hypothesized to exist. AGS should review the pertinent plans and sections of the project specifications, to evaluate conformance with the intent of the recommendations contained in this report. If the project description or final design varies from that described in this report, AGS must be consulted regarding the applicability of, and the necessity for, any revisions to the recommendations presented herein. AGS accepts no liability for any use of its recommendations if the project description or final design varies and AGS is not consulted regarding the changes. ADVANCED GEOTECHNICAL SOLUTIONS, INC. - .... ----------... - - - .. March 30, 2016 P/W 1602-03 Page 18 Report No. 1602-03-B-2 8.0 SLOPE AND LOT MAINTENANCE Maintenance of improvements is essential to the long-term performance of structures and slopes. Although the design and construction during mass grading is planned to create slopes that are both grossly and surficially stable, certain factors are beyond the control of the soil engineer and geologist. The homeowners must implement certain maintenance procedures. The following recommendations should be implemented. 8.1. 8.2. 8.3. 8.4. 9.0 Slope Planting Slope planting should consist of ground cover, shrubs and trees that possess deep, dense root structures and require a minimum of irrigation. The resident should be advised of their responsibility to maintain such planting. Lot Drainage Roof, pad and lot drainage should be collected and directed away from structures and slopes and toward approved disposal areas. Design fine-grade elevations should be maintained through the life of the structure or if design fine grade elevations are altered, adequate area drains should be installed in order to provide rapid discharge of water, away from structures and slopes. Residents should be made aware that they are responsible for maintenance and cleaning of all drainage terraces, down drains and other devices that have been installed to promote structure and slope stability. Slope Irrigation The resident, homeowner and Homeowner Association should be advised of their responsibility to maintain irrigation systems. Leaks should be repaired immediately. Sprinklers should be adjusted to provide maximum uniform coverage with a minimum of water usage and overlap. Overwatering with consequent wasteful run-off and ground saturation should be avoided. If automatic sprinkler systems are installed, their use must be adjusted to account for natural rainfall conditions. Burrowing Animals Residents or homeowners should undertake a program for the elimination of burrowing animals. This should be an ongoing program in order to maintain slope stability . LIMITATIONS • This report is based on the project as described and the information obtained from the excavations at the • approximate locations indicated on the Plate 1. The findings are based on the results of the field, laboratory, and office investigations combined with an interpolation and extrapolation of conditions between and ... • .. -.. --- beyond the excavation locations. The results reflect an interpretation of the direct evidence obtained. Services performed by AGS have been conducted in a manner consistent with that level of care and skill ordinarily exercised by members of the profession currently practicing in the same locality under similar conditions. No other representation, either expressed or implied, and no warranty or guarantee is included or intended . ADVANCED GEOTECHNICAL SOLUTIONS, INC. - - --- • .. -... - - ... ---·-• --- March 30, 2016 P/W 1602-03 Page 19 Report No. 1602-03-B-2 The recommendations presented in this report are based on the assumption that an appropriate level of field review will be provided by geotechnical engineers and engineering geologists who are familiar with the design and site geologic conditions. That field review shall be sufficient to confirm that geotechnical and geologic conditions exposed during grading are consistent with the geologic representations and corresponding recommendations presented in this report. AGS should be notified of any pertinent changes in the project plans or if subsurface conditions are found to vary from those described herein. Such changes or variations may require a re-evaluation of the recommendations contained in this report. The data, opinions, and recommendations of this report are applicable to the specific design of this project as discussed in this report. They have no applicability to any other project or to any other location, and any and all subsequent users accept any and all liability resulting from any use or reuse of the data, opinions, and recommendations without the prior written consent of AGS. AGS has no responsibility for construction means, methods, techniques, sequences, or procedures, or for safety precautions or programs in connection with the construction, for the acts or omissions of the CONTRACTOR, or any other person performing any of the construction, or for the failure of any of them to carry out the construction in accordance with the final design drawings and specifications . ADVANCED GEOTECHNICAL SOLUTIONS, INC. ... -------APPENDIX A • REFERENCES - • ---.. -- , ... - .. .. -• .. ---ADVANCED GEOTECHNICAL SOLUTIONS, INC. - - ----.. ------ - - - - .. -.. -• ... --- REFERENCES American Concrete Institute, 2002, Building Code Requirements for Structural Concrete (ACI318M-02) and Commentary (AC/ 318RM-02), AC/ International, Farmington Hills, Michigan. American Society for Testing and Materials, 2008, Annual Book of ASTM Standards, Section 4, Construction, Volume 04.08, Soil and Rock(/), ASTM International, West Conshohocken, Pennsylvania. American Society of Civil Engineers, 2013, Minimum Design Loads for Buildings and Other Structures (7-10, third printing). California Code of Regulation, Title 24, 2013 California Building Code, 3 Volumes. FEMA, Flood Insurance Rate Maps, County of San Diego, Panel 06073C0761G, dated May 16, 2012 Jennings, C.W., 1994, Fault Activity Map of California and Adjacent Areas: California Geological Survey, California Geologic Data Map No. 6, Scale l:750,000. Kennedy, M.P. and Tan, S.S., 2007. Geologic Map of the Oceanside 30' x 60' Quadrangle, California, l:100,000 Scale. United States Geological Survey, U.S. Seismic Design Maps, World Wide Web, http://earthquake.usgs.gov/designmaps/us/. ADVANCED GEOTECHNICAL SOLUTIONS, INC. - - - --- - - - ""' -.. ---- -- , ... .. - ... - APPENDIXB FIELD DATA BORING LOGS BA-1 THROUGH BA-3 ADVANCED GEOTECHNICAL SOLUTIONS, INC . I I I I I .,. 0 "' g <ri S! (!) g BORING NUMBER BA-1 PAGE 1 OF 1 ADVANCED GEOTECH.'1/ICAL SOLUTIONS, INC. CLIENT Soil Retention PROJECT NAME 2501 State Street PROJECT NUMBER_1.,_,6:.::0=2....,-0'-"3'---------------PROJECT LOCATION_C=-a=r'-"ls,.,,b=a=d,_C=A'-'-------------- DATE STARTED_,2=/2=3=/1.,_,6:...._ __ _ COMPLETED _,2=/=23=/__,__16=-------GROUND ELEVATION-'3"""6"""ft~--- GROUND WATER LEVELS: HOLE SIZE _,6:...._ _____ _ DRILLING CONTRACTOR.-'N'-'-a=t"""iv=e....,D"-'n=·ll=in=g'----------- DRILLING METHOD_T.:...:n"'· :.::o=d _____________ _ AT TIME OF DRILLING_-_--____________ _ 15 CH GP SC CHECKED BY ....,J"-A""C'-----AT END OF DRILLING_-_-_____________ _ AFTER DRILLING ________________ _ LU a. ~ffi MATERIAL DESCRIPTION LUal _j:::? a. ::J :::?z <t: (/) BU MC @6 ft. Drilling slightly harder. (/) w 3:: f-::J 0Z.J _j ::J <t: mo> 06 7-10-10 (20) ~ ~ ~ ~ w ~ z o:::~ t:9 ::J f-0 z (J f-z ~ ::J -9, (/)LU -f-0::: & oz :::?O ::J f-0 0 <t: (/) 108 15.4 76 --------------------------~~--1------4 @8 ft. SANDY CLAY, brown to grayish brown, moist, stiff. MC 12-17-34 109 18_3 93 1---0-ld_P_a_r_a_li_c _D_e_p_o_si-ts-/Q_o_p_) ___________ _... (51 ) SAND, fine to medium grained, brown to olive brown, moist, dense. @12 ft. SAND, medium to coarse grained, light gray to light olive gray, moist, dense. @14 ft. SANDY GRAVEL, gray, subrounded, up to 3" , diameter, dense. _________________ f SAND with CLAY and SILT, fine to coarse grained, light yellow to light yellowish brown, slightly moist, very dense. MC 15-18-24 109 13.0 65 (42) MC 50/6" 102 10.7 45 f-z LU f-z 0~ 0 ~ (/) LU z u::: (/) f-(/) LU f- 0::: LU I 6 CHEM, El CONSOL (!) z ii: 0 al Cl) (!) <(L.,. __________________________________________________ __, I I I .., a.. C) <Ji C) 0 -' C) z ii: 0 a, M c;> N 0 <D 5 <( a, Cl) -' a:: <( u z 0 i= z w ,-w a:: -' 5 Cl) M ~ 0 <D <D I[ ::; -' :i: 9, a.. 0 ~ Cl) w 0 S2 u ~ a:: w Cl) ;l i..i M "' ~ <D 5i I ~ ,- 0 C) ai :5 I Cl) :::, ~ Cl) ,-z (5 I ' ;!: 0 N 0 M oi M > I C) 0 -' C) z ii: 0 a, Cl) C) <( BORING NUMBER BA-2 ADVANCED GEOTECIINlrAL SOLUTIONS, INC. CLIENT Soil Retention PROJECT NAME 2501 State Street PAGE 1 OF 1 PROJECTNUMBER_1~6~0~2--=0~3 _____________ _ PROJECT LOCATION....:C,,,,a,::.rl.:.::sc:ecba,,.,d~C,.,_A_,__ ___________ _ DATESTARTED....,2~/2~3~/1~6'-----COMPLETED ~2=n=3~/1~6 __ _ GROUND ELEVATION....,3,:..:,5:...:ft_,__ __ _ HOLE SIZE ~6~------ DRILLING CONTRACTOR_,N-"a""'t'"'iv--"'e-=D=-'-n:..::·11.!!.in,.,,g~---------GROUND WATER LEVELS: DRILLING METHOD_T:...:.n""· c:::O:::..d _____________ _ AT TIME OF DRILLING_-_-____________ _ LOGGED BY ....,P....:Wc..:..M=------CHECKED BY ~J~A=C~---AT END OF DRILLING ______________ _ NOTES ____________________ _ AFTER DRILLING ________________ _ z (.) 0 I ~~ :i: c, (/) f-~ (.) <( ¢:: a. ¢:: a.o >~ w~ r?. _J (/) w 0 :::i _J (.9 w 35 0 SM GP CH 30 5 SP 25 10 SC 20 15 MATERIAL DESCRIPTION Artificial Fill -Undocumented (afu) I SIL TY to CLAYEY SAND, fine to medium grained, brown, / I wet, loose. ___________________ / @0.5 ft. GRAVEL, angular, approx. 1/2" diameter. @3 ft. CLAY with trace SAND, grayish brown, wet, soft; hole is caving. @4.5 Slightly harder drilling. Old Paralic Deposits (Qop) SAND, fine to medium grained, grayish brown, medium dense. w a. (/) w i: ffi 3: f-:::i wa:i 0z_1 _J~ _J :::i <( a. :::i mo> ~z (.) ~ <( (/) --------------------------1-~----~ SAND with CLAY and SILT, fine to coarse grained, light greenish gray to light olive, moist, dense. MC 13-37- 50/4" _ ......... __ ......_......._..___ .......... __ @16 ft. Light yellowish brown. MC 50/6" TD= 16.5 ft. NoGW ~ ~ ~ ~ UJ ~ z Q'.f-t: 'ti' 0 :::>z ~ f-w z a. ~f-r?. :::i~ ~ oz :::i ~o ~ 0 (.) (/) 116 14.0 84 102 11.3 47 f-z w f-z 0~ (.) e..., (/) w z u:: (/) f-(/) w f-a: w I b DS I I I I BORING NUMBER BA-3 PAGE 1 OF 1 AD\IANCEO GEOTECHNICAL SOLUTIONS, INC. CLIENT Soil Retention PROJECT NAME 2501 State Street PROJECTNUMBER_1~6=0=2-~0~3 _____________ _ PROJECT LOCATION_C=a=r..,_,ls=b=a=-d'-'C"-'A'-'-------------- DATESTARTED~2~n=3~/1~6=----COMPLETED ~2_/2_3_/1_6 __ _ GROUND ELEVATION 35 ft -----HOLE SIZE ....:6=------- DRILLING CONTRACTOR~N~a=t~iv~e~D~ri~lli~ng~---------GROUND WATER LEVELS: DRILLING METHOD_T~n~· ~o~d _____________ _ AT TIME OF DRILLING_-_-____________ _ CHECKED BY~J~A~C ___ _ AT END OF DRILLING_-_-_____________ _ AFTER DRILLING ________________ _ MATERIAL DESCRIPTION w ~ a.. (/) w ~ffi 3: 1--:::, !=c;::-wm 0Z..J z (..) ..J ~ ..J:::, <{ :::, -9: a..:::, mo> ~z ()~ >- <{ et: (/) 0 ~ w ~ ~ et:~ z :::, 1--0 1--Z i== (/)UJ <{ -1--et: oz :::, ~o 1--() <{ 1--z UJ 1--z~ 0~ ()~ (/) UJ z u:: ~ (/) UJ l- o:: w I l-o §l--"""--+-..,.__ ..... _____ +-_C_o-re-d-th-ro_u_g_h_5_"_A_s_p_ha-l-t;_o_v-er_4_"_c_o_n_cr-e-te_;_o_ve_r_2_"_S_a_n_d_; ---lf----+------+---+--+----1----1,-------i ~ _ over 2" Asphalt. _________________ / .............. ---1 (/) g Artificial Fill -Undocumented (afu) ~ \ SIL TY SAND with CLAY, fine to medium grained, brown, ( ~ \ slightly moist, medium dense. ___________ J BU m @2 ft. CLAYEY SAND, fine to medium grained, brown, 9 moist, medium dense. g ---------------------------,.------15 < m Cl) ...J 0:: <'l z 0 ~ ~ 25 10 0:: ...J 5 Cl) M ~ "' <O Ii: :::; ...J :f 20 15 SP SC @5 ft. SANDY CLAY, fine to medium grained sand, brown, moist, very stiff; trace white, angular gravel to 1/4" diameter. Old Paralic Deposits (Qop) SAND, fine to medium grained, brownish gray with slight orange staining, slightly moist, medium dense . SAND with some CLAY and SILT, fine to coarse grained, yellowish brown, slightly moist. MC 13-13•18 104 20.0 88 (31) MC 20-21-31 108 4.4 22 (52) MAX, DS-R OS ~ @15 ft. Slightly moist, very dense. ~1---L--....L.£...4..L.J"1..-_----1_....:T::..D_=_15-.-8.::.ft __ ....:._ ___ :...._ __________ _.L_...__.....,_ ___ ,___,__---''-----'----'------1 MC 32-50/4" 96 10.9 39 CONSOL ~ NoGW 0 S2 u ~ 0:: w Cl) ::::, ;:; ti Cl iri ~ Cl) ::::, 0 >-Cl) >-z c5 ;! 0 N g cri S! 8 ...J Cl z ii 0 m Cl) Cl <L------------------------------------------------------' - ..... -- - --... -... ----- APPENDIXC LABORATORY DATA ADVANCED GEOTECHNICAL SOLUTIONS, INC. ... .. ------ - - -- - -- "" • -- ---... - ""' • -• -.. ADVANCED GEOTECHNICAL SOLUTIONS, INC. DRY DENSITY AND MOISTURE CONTENT -ASTM D2166 Project Name: 2501 State Street Location: Carlsbad, CA Project No: 1602-03 ------- Sample Date: 2/23/16 Submittal Date: 2/29/16 Test Date: 3/2/16 Boring No. BA-1 BA-1 BA-1 Depth (ft) 4' 8' 12' Moisture 15.4 18.3 13.0 Content(%) Dry Density 108.3 109.4 108.6 (pcf) By: PWM By: PWM By: HM BA-1 BA-2 16' 12' 10.7 14.0 102.3 115.5 BA-2 BA-3 16' 5' 11.3 20.0 101.6 103.8 BA-3 BA-3 10' 15' 4.4 10.9 107.9 95.5 ... --... - - - - -• -.. - --.. ... • .. • --- ADVANCED GEOTECHNICAL SOLUTIONS, INC. EXPANSION INDEX -ASTM D4829 Project Name: 2501 State Street Location: Carlsbad, CA File No: 1602-03 Date: 3/6/16 Excavation: BA-1 -------- Depth: 0-3' -------- Des c rip ti on: Grayish Brown Sandy Clay By: H-M Expansion Index -ASTM D4829 Initial Dry Density (pcf): 103.4 Initial Moisture Content(%): 12.0 Initial Saturation (%): 51.5 Final Dry Density (pcf): 106.3 Final Moisture Content(%): 21.5 Final Saturation (%): 92.3 Expansion Index: 103 Potential Expansion: High ASTM 04829 -Table 5.3 Expansion Index Potential Expansion 0-20 Very Low 21 -50 Low 51 -90 Medium 91 -130 High >130 Very High ,.., - - - - - - ·-----.. • ---• ---- ADVANCED GEOTECHNICAL SOLUTIONS, INC. MAXIMUM DENSITY -ASTM D1557 Excavation: BA-3 ---------Depth: 1-4' --------- Project Name: 2501 State Street Location: Carlsbad, CA Project No.: 1602-03 Des c rip ti on: Dark Brown Clayey Sand ---------Date: 2/26/2016 135,0 130,0 Ci:" 8,_ 125.0 -~ "' C ~ 120,0 ~ C 115.0 110.0 105.0 Test Number Dry Density (pcf) Moisture Content(%) Method 1 113.3 9.9 A 2 118.6 12.5 Max Density By: H-M 3 118.0 14.5 4 112.1 15.8 -+--Test Curve Zero Air Voids Curves -----SG=2.6 ---SG=2.7 100.0 ._ ____ .. ____ ....,..,_ ____ ... ____ ...,. _____ ,... ____ __ 0.0 5.0 10.0 15.0 20.0 25.0 30.0 Moisture(%) Maximum Density 119.0 pcf Optimum Moisture 13.5 % ----- -- .. - , ... ... - - .. - --- - .. • .. • ---- ADVANCED GEOTECHNICAL SOLUTIONS, INC . DIRECT SHEAR -ASTM D3080 Project Name: 2501 State St. -----------Excavation: BA-2 -------- Location: Carlsbad, CA Depth: 12' ------- Project No.: 1502-03 -----------Sample Type: Undisturbed Date: 3/4/16 By: HM Samples Tested 1 2 3 Method: Drained Normal Stress (psf) 1000 2000 4000 Consolidation: Yes Maximum Shear Stress (psf) 1392 2436 3504 Saturation: Yes Ultimate Shear Stress (psf) 792 1356 2640 Shearing Rate (in/min): 0.04 Initial Moisture Content(%) 14.0 14.0 14.0 Initial Dry Density (pcf) 108.7 105.4 105.6 Friction Angle, phi (deg) Cohesion (psf) Peak 34 750 Ultimate 32 150 4000 3500 3000 ~ 2500 ~ "' "' Qj 2000 ... ... VI ... RI Qj .J::. 1500 VI 1000 / V / ., ., , ., / ., V ., 1r / ., j ]" ( V ., ., / ., ., / ., ., / ., , ., vr ., ~ or ., 0 Peak .,,. ~ --:/ ., -Peak Jr' ., D Ultimate 500 ., -. ---Ultimate ., 0 ., I I I .. 0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 5500 Shear Stress v. Displacement 4000 ....... --------'---------, -----2000 3500 +----,-,-,,-.------------! ... ,/· ":/ t.·········· ······ ... _ 3000 -----------"'-----'t; ····-.... -;' 2500 +--,--~.,.,-=-,----- VI f., ' --1000 t 2000 -1--......,' .;...' ___ ',,,,_ _______ ----i C,I) } '' m 1500 +-...," .... · _______ ,....;.'----==--------1 .c ,'f~ --- "' 1000 -f-L-¥'-----___;::.....::::-----------1 500 /..( N .. ............... 4000 Normal Stress (psf) _0.02 .J-_______ :::;,_ ___ --1 5 5 0.01 +--_.,.....,_..,,.... _______ --I +' Ill E o.oo -tc,s-,=~--------------1 .E ~-0.01 --------------! iii :e-0.02 ------------- Cl> >_0_03 0.00 0.10 0.20 0.30 0.40 0.00 0.05 0.10 0.15 0.20 0.25 0.30 Displacement (in) Displacement (in) -... -- .. .. - - ---- - .. • -• .. -... --- ADVANCED GEOTECHNICAL SOLUTIONS, INC. DIRECT SHEAR -ASTM D3080 Project Name: 2501 State St. Excavation: BA-3 --------Location: Carlsbad, CA Depth: 10' -------- Project No.: _1_6_02_-_0_3 ______ _ Sam p I e Type: Undisturbed Date: 3/5/16 By: HM Samples Tested 1 2 3 Method: Drained Normal Stress (psf} 1000 2000 4000 Consolidation: Yes ----Maximum Shear Stress (psf) 960 1404 2688 Saturation: Yes ----Ultimate Shear Stress (psf) 708 1356 2196 Shearing Rate (in/min): 0.04 ----Initial Moisture Content (%) 4.4 4.4 4.4 Initial Dry Density (pcf} 103.0 104.0 101.9 Friction Angle, phi (deg) Cohesion (psf) Peak 31 300 Ultimate 28 175 t;:" "' C. 3500 3000 2500 °;' 2000 "' QI ... .... Ill Ri 1500 QI .c Ill 1000 500 0 V. .;, ,,, V:,,, -,,, .. / / ,,, ,,, ~ I ,,, ,,, ,,, / ,,, ,,, V,,, ,,, a,,, / / / ,,, . ,,, ,,, V ,,, .-/ .,, ,,, .. "'[ J ,,, ,,, ,,, ,,, ,,, 0 Peak - --Peak D Ultimate - ---Ultimate I I 0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 Normal Stress {psf) Shear Stress v. Displacement 3000 -,---------"--------, . ········,., 2500 -------~...,.--................. 4000 ·•·• ....... , ! 2000 --------------2000 "' "' --1000 ~ 1500 --------------------1 "' ---------... '" l 1000 -t-1----:::::::::::==::::---------, 111 500 ..,...),..,,/(_,. _-___________ --1 N' 0 -1-l ....................... _.,_ ........ _.__ ............... ..__._...__ ......... ""' 0.00 0.10 0.20 0.30 0.40 Displacement (in) Vertical Deformation v. Displacement 0.03 ---------'------ _0.02 t---------=:::====--i :§. ~···························· I 0.01 -----/ .. -.... -.... -..... .,,.····""··· -"'--_-_-_ -__ -_-_-_----1 E 0.00 -k:----,""""'"----.,........;;;._-----1 ... ~~------.E ~-0.Dl +--------------1 ia :e-0.02 +--------------1 GJ ·····•••·••••·••· 4000 >-0.03 -----2000 --1000 0.00 0.05 0.10 0.15 0.20 0.25 0.30 Displacement (in) ------- --.. .. .. - ..... --- ---.. ----- ADVANCED GEOTECHNICAL SOLUTIONS, INC. DIRECT SHEAR -ASTM D3080 Project Name: 2501 State St. ------------Location: Carlsbad, CA Project No.: 1602-03 ------------Date: 3/6/16 Samples Tested 1 2 Normal Stress (psf} 1000 2000 3 4000 Excavation: BA-3 --------Depth: 1-4' ....;_...;__ _____ _ Sample Type: Remolded to 90% By: HM Method: Drained Consolidation: Yes Maximum Shear Stress (osf) 936 1536 1992 Saturation: Yes ----Ultimate Shear Stress (psf} 912 1524 1980 Shearing Rate (in/min): _.....;0.....;.0_4_ Initial Moisture Content(%) 13.5 13.5 13.5 Initial Dry Density (pcf} 106.2 106.2 106.2 Friction Angle, phi (deg) Cohesion (psf) Peak 23 550 Ultimate 22 500 3500 3000 2500 ~ '; 2000 Ill Qj ... ti la 1500 ,r, ~ ~ ... ........-:: ~ =------ ~ ... ~--·~ ... Qj ..c VI ~ ~ ~ ... i, 1000 500 0 Peak -~ t -v---Peak ... D Ultimate - ---Ultimate 0 I I ' 0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 Shear Stress v. Displacement 2500 -----------------, ;;:- "' a. 2000 -1-------... -.... -.... -.... -. .. ---..... -·· .. ··· ';;;' 1500 -1--------=---~ ~ / .,., ... - ................. 4000 -----2000 --1000 t;, ! ,/ I 1000 t1-_;.\i1:r-:, ============-----, 500 i•v 0.00 0.10 0.20 0.30 0.40 Displacement (in) Normal Stress (psf) Vertical Deformation v. Displacement 0.03 -------------, -0.02 +-------------1 :§. 5 0.01 +-------------1 1 0.00 .L ........... -=-.. -... "" . .-:-== .. :-=.-:-.=~.=---.:=::.=:: -= .... -= .. :-= ... --:=._=_=_=_~-I ~-0.01 -t--------------i "iii "f-0.02 -t--------------i cu ................. 4000 >_0_03 -----2000 --1000 -0.04 +'-...... __ ....... __ ......... -+-'" ........ -+-'" ....... --+-" ....... ""' 0.00 0.05 0.10 0.15 0.20 0.25 0.30 Displacement (in) - • -- ----- - --- - - - -- • --- • --- ADVANCED GEOTECHNICAL SOLUTIONS, INC. CONSOLIDATION -ASTM D2435 Excavation: BA-1 Project Name: 2501 State Street Location: Carlsbad, CA Project No: 1602-03 --------Depth: 12' --------Des c rip ti on: -----------------Date: 3/2/2016 By: HM -~ 0 -C 0 .. cu 'C 0 II) C 0 0 0.1 1 0 -~"-- -1 -2 -3 -4 -* -5 Test Description: Water Content, w Void Ratio, e Saturation, S Dry Density (pcf) Wet Density (pcf) ~-... * Consolidation-Pressure Curve Normal Pressure (ksf) 1 10 i I ..... ..... ~\.. ~-water added ·~ ... ... ... i I ~ , ... . --* * ~ ... .~ • .. I ~ I Before Test After Test 13.0% 19.6% 0.70 0.64 50% 83% 99.2 102.8 112.0 122.9 100 I i ! 7 - - -- - .... - .... • -.... - --.. .. • ... • --.. --- ADVANCED GEOTECHNICAL SOLUTIONS, INC. CONSOLIDATION -ASTM D2435 Excavation: BA-3 Project Name: 2501 State Street Location: Carlsbad, CA Project No: 1602-03 ---------Depth: 15' ---------Des c rip ti on: ------------------Date: 3/2/2016 By: HM -~ 0 -C 0 .:; ca "C 0 ti) C 0 0 0.1 1 0 >--.. -1 :=-.. -2 -3 ,....._. Consolidation-Pressure Curve Normal Pressure (ksf) 1 10 ~ "' ~-.... i I -I .... water added , '-I -,. ' -I i ~ -.... ... ' ,. ,. " ~ ,. ~ ~ i t-• \: I I I 100 I ' I I -4 +-----+--+---+--+--+--t-----+--++----+--+----+---+--+----+---1--+-a---+-----+-+-+---+--t-+-1 i I I I -5 Test Description: Before Test After Test Water Content, w 10.9% 15.1% Void Ratio, e 0.46 0.45 Saturation, S 64% 92% Dry Density (pcf) 115.2 116.5 Wet Density (pcf) 127.7 134.1 -.. -- ANAHEIM TEST LAB, INC 3008 ORANGE A VENUE SANT A ANA, CALIFORNIA 92707 PHONE (714) 549-7267 Advanced Geotechnical Solutions, Inc -2842 Walnut Avenue, Suite C-1 ,. Tustin, CA 92780 • Attn: Sean Donovan • J.N.: 1602-03 _ Project: 2501 State Street Carlsbad ---- PH ,_ BA-1 @0-3' 7.7 - .. -.. • -.. --- ANALYTICAL REPORT CORROSION SERIES SUMMARY OF DAT A SOLUBLE SULFATES per CA. 417 ppm 148 SOLUBLE CHLORIDES per CA. 422 ppm 74 DATE: 03/07 /16 P.O. NO.: Verbal LAB NO.: B-9160 SPECIFICATION: CA-417 /422/643 MATERIAL: Soil MIN. RESISTIVITY per CA. 643 ohm-cm 1,300 WES BRIDGER CHEMIST --- - - .. - -.... - - - - - ... ... .. • ... -.. -... - APPENDIXD GENERAL EARTHWORK SPECIFICATIONS AND GRADING GUIDELINES ADVANCED GEOTECHNICAL SOLUTIONS, INC . -- ,_ --- - -,,.. ... - ,_ ,,, .. - • .. • .... -- - GENERAL EARTHWORK SPECIFICATIONS I. General A. General procedures and requirements for earthwork and grading are presented herein. The earthwork and grading recommendations provided in the geotechnical report are considered part of these specifications, and where the general specifications provided herein conflict with those provided in the geotechnical report, the recommendations in the geotechnical report shall govern. Recommendations provided herein and in the geotechnical report may need to be modified depending on the conditions encountered during grading. B. The contractor is responsible for the satisfactory completion of all earthwork in accordance with the project plans, specifications, applicable building codes, and local governing agency requirements. Where these requirements conflict, the stricter requirements shall govern. C. It is the contractor's responsibility to read and understand the guidelines presented herein and in the geotechnical report as well as the project plans and specifications. Information presented in the geotechnical report is subject to verification during grading. The information presented on the exploration logs depicts conditions at the particular time of excavation and at the location of the excavation. Subsurface conditions present at other locations may differ, and the passage of time may result in different subsurface conditions being encountered at the locations of the exploratory excavations. The contractor shall perform an independent investigation and evaluate the nature of the surface and subsurface conditions to be encountered and the procedures and equipment to be used in performing his work. D. The contractor shall have the responsibility to provide adequate equipment and procedures to accomplish the earthwork in accordance with applicable requirements. When the quality of work is less than that required, the Geotechnical Consultant may reject the work and may recommend that the operations be suspended until the conditions are corrected. E. Prior to the start of grading, a qualified Geotechnical Consultant should be employed to observe grading procedures and provide testing of the fills for conformance with the project specifications, approved grading plan, and guidelines presented herein. All remedial removals, clean-outs, removal bottoms, keyways, and subdrain installations should be observed and documented by the Geotechnical Consultant prior to placing fill. It is the contractor's responsibility to apprise the Geotechnical Consultant of their schedules and notify the Geotechnical Consultant when those areas are ready for observation. F. The contractor is responsible for providing a safe environment for the Geotechnical Consultant to observe grading and conduct tests. II. Site Preparation A. Clearing and Grubbing: Excessive vegetation and other deleterious material shall be sufficiently removed as required by the Geotechnical Consultant, and such materials shall be properly disposed of offsite in a method acceptable to the owner and governing agencies. Where applicable, the contractor may obtain permission from the Geotechnical Consultant, owner, and governing agencies to dispose of vegetation and other deleterious materials in designated areas onsite. ADVANCED GEOTECHNICAL SOLUTIONS, INC. - -- -.. -- ""' • .. • -• ... .. -- B. Unsuitable Soils Removals: Earth materials that are deemed unsuitable for the support of fill shall be removed as necessary to the satisfaction of the Geotechnical Consultant. C. Any underground structures such as cesspools, cisterns, mining shafts, tunnels, septic tanks, wells, pipelines, other utilities, or other structures located within the limits of grading shall be removed and/or abandoned in accordance with the requirements of the governing agency and to the satisfaction of the Geotechnical Consultant. D. Preparation of Areas to Receive Fill: After removals are completed, the exposed surfaces shall be scarified to a depth of approximately 8 inches, watered or dried, as needed, to achieve a generally uniform moisture content that is at or near optimum moisture content. The scarified materials shall then be compacted to the project requirements and tested as specified. E. All areas receiving fill shall be observed and approved by the Geotechnical Consultant prior to the placement of fill. A licensed surveyor shall provide survey control for determining elevations of processed areas and keyways. III. Placement of Fill A. Suitability of fill materials: Any materials, derived onsite or imported, may be utilized as fill provided that the materials have been determined to be suitable by the Geotechnical Consultant. Such materials shall be essentially free of organic matter and other deleterious materials, and be of a gradation, expansion potential, and/or strength that is acceptable to the Geotechnical Consultant. Fill materials shall be tested in a laboratory approved by the Geotechnical Consultant, and import materials shall be tested and approved prior to being imported. B. Generally, different fill materials shall be thoroughly mixed to provide a relatively uniform blend of materials and prevent abrupt changes in material type. Fill materials derived from benching should be dispersed throughout the fill area instead of placing the materials within only an equipment-width from the cut/fill contact. C. Oversize Materials: Rocks greater than 8 inches in largest dimension shall be disposed of offsite or be placed in accordance with the recommendations by the Geotechnical Consultant in the areas that are designated as suitable for oversize rock placement. Rocks that are smaller than 8 inches in largest dimension may be utilized in the fill provided that they are not nested and are their quantity and distribution are acceptable to the Geotechnical Consultant. D. The fill materials shall be placed in thin, horizontal layers such that, when compacted, shall not exceed 6 inches. Each layer shall be spread evenly and shall be thoroughly mixed to obtain near uniform moisture content and uniform blend of materials. E. Moisture Content: Fill materials shall be placed at or above the optimum moisture content or as recommended by the geotechnical report. Where the moisture content of the engineered fill is less than recommended, water shall be added, and the fill materials shall be blended so that near uniform moisture content is achieved. If the moisture content is above the limits specified by the Geotechnical Consultant, the fill materials shall be aerated by discing, blading, or other methods until the moisture content is acceptable . ADVANCED GEOTECHNICAL SOLUTIONS, INC. .. --... .. .. • .. ---------- - .. • .. • .. • --- F. Each layer of fill shall be compacted to the project standards in accordance to the project specifications and recommendations of the Geotechnical Consultant. Unless otherwise specified by the Geotechnical Consultant, the fill shall be compacted to a minimum of 90 percent of the maximum dry density as determined by ASTM Test Method: Dl557-09 . G. Benching: Where placing fill on a slope exceeding a ratio of 5 to 1 (horizontal to vertical), the ground should be keyed or benched. The keyways and benches shall extend through all unsuitable materials into suitable materials such as firm materials or sound bedrock or as recommended by the Geotechnical Consultant. The minimum keyway width shall be 15 feet and extend into suitable materials, or as recommended by the geotechnical report and approved by the Geotechnical Consultant. The minimum keyway width for fill over cut slopes is also 15 feet, or as recommended by the geotechnical report and approved by the Geotechnical Consultant. As a general rule, unless otherwise recommended by the Geotechnical Consultant, the minimum width of the keyway shall be equal to 1/2 the height of the fill slope. H. Slope Face: The specified minimum relative compaction shall be maintained out to the finish face of fill and stabilization fill slopes. Generally, this may be achieved by overbuilding the slope and cutting back to the compacted core. The actual amount of overbuilding may vary as field conditions dictate. Alternately, this may be achieved by backrolling the slope face with suitable equipment or other methods that produce the designated result. Loose soil should not be allowed to build up on the slope face. If present, loose soils shall be trimmed to expose the compacted slope face. I. Slope Ratio: Unless otherwise approved by the Geotechnical Consultant and governing agencies, permanent fill slopes shall be designed and constructed no steeper than 2 to 1 (horizontal to vertical). J. Natural Ground and Cut Areas: Design grades that are in natural ground or in cuts should be evaluated by the Geotechnical Consultant to determine whether scarification and processing of the ground and/or overexcavation is needed. K. Fill materials shall not be placed, spread, or compacted during unfavorable weather conditions. When grading is interrupted by rain, filing operations shall not resume until the Geotechnical Consultant approves the moisture and density of the previously placed compacted fill. IV. Cut Slopes A. The Geotechnical Consultant shall inspect all cut slopes, including fill over cut slopes, and shall be notified by the contractor when cut slopes are started. B. If adverse or potentially adverse conditions are encountered during grading, the Geotechnical Consultant shall investigate, evaluate, and make recommendations to mitigate the adverse conditions . C. Unless otherwise stated in the geotechnical report, cut slopes shall not be excavated higher or steeper than the requirements of the local governing agencies. Short-term stability of the cut slopes and other excavations is the contractor's responsibility . V. Drainage A. Backdrains and Subdrains: Backdrains and subdrains shall be provided in fill as recommended by the Geotechnical Consultant and shall be constructed in accordance with the governing agency and/or recommendations of the Geotechnical Consultant. The location of subdrains, especially outlets, shall be surveyed and recorded by the Civil Engineer. ADVANCED GEOTECHNICAL SOLUTIONS, INC. ..... - - - ... - --- • ---.. .. --... --- B. Top-of-slope Drainage: Positive drainage shall be established away from the top of slope. Site drainage shall not be permitted to flow over the tops of slopes. C. Drainage terraces shall be constructed in compliance with the governing agency requirements and/or in accordance with the recommendations of the Geotechnical Consultant. D. Non-erodible interceptor swales shall be placed at the top of cut slopes that face the same direction as the prevailing drainage. VI. Erosion Control A. All finish cut and fill slopes shall be protected from erosion and/or planted in accordance with the project specifications and/or landscape architect's recommendations. Such measures to protect the slope face shall be undertaken as soon as practical after completion of grading . B. During construction, the contractor shall maintain proper drainage and prevent the ponding of water. The contractor shall take remedial measures to prevent the erosion of graded areas until permanent drainage and erosion control measures have been installed. VII. Trench Excavation and Backfill A. Safety: The contractor shall follow all OSHA requirements for safety of trench excavations. Knowing and following these requirements is the contractor's responsibility. All trench excavations or open cuts in excess of 5 feet in depth shall be shored or laid back. Trench excavations and open cuts exposing adverse geologic conditions may require further evaluation by the Geotechnical Consultant. If a contractor fails to provide safe access for compaction testing, backfill not tested due to safety concerns may be subject to removal. B. Bedding: Bedding materials shall be non-expansive and have a Sand Equivalent greater than 30. Where permitted by the Geotechnical Consultant, the bedding materials can be densified by jetting. C. Backfill: Jetting of backfill materials is generally not acceptable. Where permitted by the Geotechnical Consultant, the bedding materials can be densified by jetting provided the backfill materials are granular, free-draining and have a Sand Equivalent greater than 30. VIII. Geotechnical Observation and Testing During Grading A. Compaction Testing: Fill shall be tested by the Geotechnical Consultant for evaluation of general compliance with the recommended compaction and moisture conditions. The tests shall be taken in the compacted soils beneath the surface if the surficial materials are disturbed. The contractor shall assist the Geotechnical Consultant by excavating suitable test pits for testing of compacted fill. B. Where tests indicate that the density of a layer of fill is less than required, or the moisture content not within specifications, the Geotechnical Consultant shall notify the contractor of the unsatisfactory conditions of the fill. The portions of the fill that are not within specifications shall be reworked until the required density and/or moisture content has been attained. No additional fill shall be placed until the last lift of fill is tested and found to meet the project specifications and approved by the Geotechnical Consultant. C. If, in the opinion of the Geotechnical Consultant, unsatisfactory conditions, such as adverse weather, excessive rock or deleterious materials being placed in the fill, insufficient equipment, excessive rate of fill placement, results in a quality of work that is unacceptable, the consultant shall notify the contractor, ADVANCED GEOTECHNICAL SOLUTIONS, INC. - - - - -- - .. - • • ... • .. -... ---... --- and the contractor shall rectify the conditions, and if necessary, stop work until conditions are satisfactory. D. Frequency of Compaction Testing: The location and frequency of tests shall be at the Geotechnical Consultant's discretion. Generally, compaction tests shall be taken at intervals not exceeding two feet in fill height and 1,000 cubic yards of fill materials placed. E. Compaction Test Locations: The Geotechnical Consultant shall document the approximate elevation and horizontal coordinates of the compaction test locations. The contractor shall coordinate with the surveyor to assure that sufficient grade stakes are established so that the Geotechnical Consultant can determine the test locations. Alternately, the test locations can be surveyed and the results provided to the Geotechnical Consultant. F. Areas of fill that have not been observed or tested by the Geotechnical Consultant may have to be removed and recompacted at the contractor's expense. The depth and extent of removals will be determined by the Geotechnical Consultant. G. Observation and testing by the Geotechnical Consultant shall be conducted during grading in order for the Geotechnical Consultant to state that, in his opinion, grading has been completed in accordance with the approved geotechnical report and project specifications. H. Reporting of Test Results: After completion of grading operations, the Geotechnical Consultant shall submit reports documenting their observations during construction and test results. These reports may be subject to review by the local governing agencies . ADVANCED GEOTECHNICAL SOLUTIONS, INC. -\-- BA-2 0-8' afu 8-16.5' Qop TD= 16.5' NoGW No Caving BA-3 0-10'afu 10-15.8' Qop TD= 15.8' NoGW l· ,h_ •• ~~ {' I. >' ' I I . . . . . ti / •··• • > ,.,,f,s,,/ .afu .. {Qop} EX BLDG. (36.5 FF) BA-1 0-9' afu 9-19.9' Qop TD= 19.9' NoGW 20 10 0 LEGEND PROPERTY LINE -fr.-- RIGHT OF WAY LINE -R/W· - STREET CENTERLINE -i-- PROP. BUILDING OUTLINE PZZZZJ PROP. CONCRETE I . . : I ~----;-;~~= PROP. PERVIOUS PAVER ~QP.$~J4,~ Geotechnical legend: BA-2G afu Qop Approximate location of Exploratory Boring Geologic Contact (Queried where uncertain, dotted where buried) Artificial Fill -Undocumented Old Paraiic Deposits (Bracketed where buried) Plate 1 Geologic Map and Exploration location Plan ADVANCED GEOTECliNICAl SOLUTIONS, INC. Project: P/\,'IJ 1602-03 20 SCALE: 1 "=20' Report: 1602-03-B-2 40 Date: March 2016 60 u, :E :::::, C oca z Cl) :e (.) 0 Oc z Check By Drawn By 0 0 DW Scale 1" = 20' Job Number 149417 PREPARED BY: NAME: 1--w w a: I-- (/) w ~ I-- (/) ,..... 0 LO C\I MICHAEL BAKER INTERNATIONAL ADDRESS: 5050 AVENIDA ENCINAS SUITE 260 CARLSBAD, CALIFORNIA 92008 (760) 476-9193 CONTACT: DAVID WIENER M icf:lael Baker INTERNATIONAL 5050 Avenida Encinas, Suite 260 Carlsbad, CA 92008 Phone: (760) 476-9193 MBAKERINTL.COM SHEET TITLE: PRELIMINARY CIVIL SITE PLAN REVISION 1: ORIGINAL DATE: 3/4/2016 --'-'------ SHEET C-1 N D:'. w z w 3: D -0 I 0.. (/) I ,..._ -ST ~ / > __J D / D z <( .7 D D <( ~ (/) 0 D z 0 (.) 1-w w ~ (/) w l- e" (/)I r--v -Ol ST / >"' <( 0 ;;;- :r: