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HomeMy WebLinkAbout6608; Northwest Quadrant Drainage Improvements; Northwest Quadrant Storm Drain Crest Dr; 2008-06-30Geotechnical and Environmental Sciences Consultants GEOTECHNICAL EVALUATION CREST DRIVE STORM DRAIN CARLSBAD, CALIFORNIA M li RECEIVED JUL • ENGINEERING DEPARTMENT PREPARED FOR: City of Carlsbad 1635 Faraday Avenue Carlsbad, Califomia 92008 PREPARED BY: Ninyo & Moore Geotechnical and Environmental Sciences Consultants 5710Ruffin Road San Diego, Califomia 92123 June 30,2008 Project No. 106332001 II hi 5710 Ruffin Road • San Diego. California 92123 • Phone (858/576-1 000 • Fax f858J 576-9600 San Dieqo • Wine - Ontario • Los Anqeles • Oakland • Las Veqas • Carson City • Phoenix • Denver pi Georechn;caJ and EnvironmenraJ Sciences Consuftanrs p in P II June 30, 2008 Project No. 106332001 Ms. Sherri Howard City of Carlsbad 1635 Faraday Avenue Carlsbad, Califomia 92008 Subject: Geotechnical Evaluation Crest Drive Storm Drain Carlsbad, Califomia Dear Ms. Howard: In accordance with your authorization, we have performed a subsurface evaluation for the pro- posed Crest Drive storm drain in Carlsbad, Califomia. This report presents our findings and conclusions regarding the geotechnical conditions within the project area and our recommenda- tions regarding design and construction of the proposed improvements. We appreciate the opportunity to be of service on this project. Respectfully submitted, ^ . NINYO & MOORE Emil Rudolph, RE., G.E. Senior Engineer MAH/ER/FOM/kh Distribution; (6) Addressee Francis O. Moreland, C.E.G. Senior Geologist 5710 Ruffin Road • San Diego, California 92123 - Phone (858] 576-1000 - Fax (858) 576-9600 San Dieqo • Irvine • Ontario • Los Anqeles • Oakland • Las Vegas • Carson City • Phoenix • Denver Crest Drive Storm Drain June 30, 2008 Carlsbad, Califomia Project No. 106332001 TABLE OF CONTENTS Page p. 1. INTRODUCTION 1 ^ 2. SCOPE OF SERVICES 1 3. SITE AND PROJECT DESCRIPTION 1 km 4. SUBSURFACE EVALUATION AND LABORATORY TESTING 2 5. GEOLOGY AND SUBSURFACE CONDITIONS 2 ^ 5.1. Regional Geologic Setting 3 5.2. Site Geology 3 p. 5.2.1. Fill 3 ^ 5.2.2. Old Paralic Deposits (formerly referred to as Terrace Deposits) 4 5.2.3. Santiago Formation 4 ^ 5.3. Rippability 4 ^ 5.4. Groundwater 4 5.5. Faulting and Seismicity 4 ^ 5.5.1. Liquefaction and Seismically Induced Settlement 5 ^ 5.6. Landsliding 5 6. CONCLUSIONS 5 ^ 7. RECOMMENDATIONS 6 7.1. Pre-Constmction Conference and Health and Safety Plan 6 7.2. Excavation Characteristics .' 6 ^ 7.3. Temporary Excavations, Braced Excavations and Shoring 7 7.4. Micro-Tunneling/Jack-and-Bore 8 7.5. Excavation Bottom Stability 9 ^ 7.6. Modulus of Soil Reaction 10 7.7. Pipe Bedding 10 7.8. Trench Backfill 11 H 7.9. Backfill Placement and Compaction 11 7.10. Corrosion 12 P 7.11. Concrete 12 ii 7.12. Pavement Reconstmction 13 ^ 8. CONSTRUCTION OBSERVATION 13 li 9. LIMITATIONS 14 In P m te 10. SELECTED REFERENCES 16 Table Table 1 - Loading on Jack-and-Bore Segment of Pipeline 9 106332001 RCresldoc m te te «* te P te Crest Drive Storm Drain June 30, 2008 Carlsbad, Califomia Project No. 106332001 Figures Figure 1 - Site Locafion Map Figure 2 - Geotechnical Map Figure 3 - Fault Location Map Figure 4 - Lateral Earth Pressures for Braced Excavations Figure 5 - Thmst Block Lateral Earth Pressure Diagram Appendices Appendix A - Boring Logs Appendix B - Laboratory Testing Appendix C - Typical Earthwork Guidelines 106332001 RCresl doc te p te Crest Drive Storm Drain June 30, 2008 Carlsbad, Califomia Project No. 106332001 1. INTRODUCTION In accordance with your request, we have perfonned a geotechnical evaluation for the proposed Crest Drive Storm Drain in the City of Carlsbad, Cahfomia (Figure 1). The purpose of this study was to evaluate the general soil and geologic conditions along the proposed alignment and to develop geo- technical recommendations regarding the design and construction of the project. This report presents our findings, conclusions, and recommendations with respect to the proposed alignment. 2. SCOPE OF SERVICES The scope of services for this study included the following: • Reviewing readily available published and in-house geotechnical literature, topographic maps, geologic maps, fault maps, stereoscopic aerial photographs, and a site plan for the project. • Performing a field reconnaissance of the proposed alignment to observe site conditions and to locate and mark proposed exploratory borings. Underground Service Alert (USA) was no- tified to mark underground utilities at the proposed boring locations. • Obtaining a San Diego County Department of Environmental Health (DEH) boring permit, an encroachment permit for the City of Carlsbad, and Traffic Control plans. • Performing a subsurface evaluation consisting of the drilling, logging, and sampHng of three exploratory borings with a hollow-stem auger drill rig. Relatively undisturbed and bulk samples were obtained at selected intervals from the borings. • Performing laboratory testing of selected soil samples. • Compiling and performing geotechnical analysis of the field and laboratory data. • Preparing this report presenting the results of our background review, reconnaissance, sub- surface exploration, laboratory testing, and data analyses to provide recommendations regarding the geotechnical aspects of the pipeline design and constmction. P 3. SITE AND PROJECT DESCRIPTION te . . The site is located on Crest Drive and eastward to Monroe Street within a residential commmiity in F the City of Carlsbad, Cahfomia (Figure 1). Topographically, the elevation on Crest Drive is ap-te proximately 185 feet above mean sea level (MSL) and elevation at the bottom of the slope along 106332001 RCrcsldoc te P P te Crest Drive Storm Drain June 30, 2008 Carlsbad, Califomia Project No. 106332001 Monroe Street is approximately 115 feet above MSL. Vegetafion along the ahgnment not in road- ways generally consists of grass, weeds, bmsh, and trees. Based on discussions and review of preliminary project plans, we understand the project consists of the proposed constmction of approximately 540 feet of new 18-inch stonn drain along the north side of the southem portion of Crest Drive, and extending eastward, down an existing slope, to a storm drain on Monroe Street. The portion of the storm drain extending fi-om Crest Drive to Monroe Street will be approximately 190 feet long. We understand that the storm drain will be constructed by cut and cover, trenchless methods, or a combination of the two. The storm drain is proposed to be on the order of approximately 10 feet deep. 4. SUBSURFACE EVALUATION AND LABORATORY TESTING Our subsurface exploration was conducted on June 6, 2008. The subsurface evaluation consisted of the drilling, logging, and sampling of three 8-inch diameter exploratory borings. The explora- tory borings were advanced to depths of up to 56 feet below existing grade. Drive and bulk soil samples were obtained from the borings. The samples were then transported to our in-house geo- technical laboratory for testing. The approximate locations of the exploratory borings are shown on Figure 2. Logs of the borings are included in Appendix A. Laboratory testing of representative soil samples included in-situ dry density and moisture con- tent, sieve analyses, shear strength, and soil corrosivity The results of the in-situ dry density and moisture content tests are presented on the boring logs in Appendix A. The results of the other laboratory tests performed are presented in Appendix B. P te 5. GEOLOGY AND SUBSURFACE CONDITIONS Our findings regarding regional and site geology, including faulting and seismicity, landslides, ii rippability (excavatability), and groundwater conditions at the subject site are provided in the following sections. 106332001 RCrcsl.doc P m p te F te p te c Crest Drive Storm Drain June 30, 2008 Carlsbad, Califomia Project No. 106332001 5.1. Regional Geologic Setting The project area is situated in the coastal foothill section of the Peninsular Ranges Geomor- phic Province. This geomorphic province encompasses an area that extends approximately 900 miles fi-om the Transverse Ranges and the Los Angeles Basin south to the southem tip of Baja Cahfomia (Norris and Webb, 1990; Harden, 1998). The province varies in width fi-om approximately 30 to 100 miles. In general, the province consists of mgged mountains under- lain by Jurassic metavolcanic and metasedimentary rocks, and Cretaceous igneous rocks of the southem Califorma batholith. The portion of the province in San Diego Coimty that includes the project area consists generally of Quatemary and Tertiary sedimentary rock. p The Peninsular Ranges Province is traversed by a group of sub-parallel faults and fault te zones trending roughly northwest. Several of these faults, which are shown on Figure 3, are p considered active faults. The Elsinore, San Jacinto and San Andreas faults are active fault te systems located northeast of the project area and the Rose Canyon, Agua Blanca-Coronado *i Bank, and San Clemente faults are active faults located west of the project area. Major tec- tome activity associated with these and other faults within this regional tectonic fi-amework consists primarily of right-lateral, strike-slip movement. Further discussion of faulting rela- te tive to the site is provided in the Faulting and Seismicity section of this report. 5.2. Site Geology Geologic units encountered during our reconnaissance and subsurface evaluation included fill and old parahc deposits. Generahzed descriptions of the earth units encountered are presented in the subsequent sections. More detailed descriptions are provided on the boring logs in Appendix A. 5.2.L Fill Fill was encountered in exploratory boring B-3 along Momoe Street from the ground surface to the depth explored of approximately 11.5 feet. As encountered, the fill gener- ally consisted of reddish brown, moist, medium dense, sihy sand with iittie clay interlayered with light gray silty coarse sand. P 106333001 RCrcsldoc te te m te F te p te p te *• te p te Crest Drive Storm Drain June 30, 2008 Carlsbad, Califomia Project No. 106332001 5.2.2. Old Paralic Deposits (formerly referred to as Terrace Deposits) Old paralic deposits generally comprise the materials encountered along the Crest Drive portion of the storm drain alignment. Old paralic deposits were encountered in boring B-1 from the ground surface to the depth explored, and in boring B-2 from grade to ap- proximately 41 feet below ground surface. In general, the old paralic deposits consisted of reddish brown, damp to moist, medium dense to very dense, silty fine sand. 5.2.3. Santiago Formation Materials of the Santiago Formation were encountered in boring B-2 below the old paralic deposits at a depth of approximately 41 feet. In general, the materials of the Santiago Formation consisted of olive gray, damp, weakly to moderately cemented, silty sandstone. 5.3. Rippability Based on our site reconnaissance and subsurface exploration, the on-site materials are ex- pected to be rippable with heavy-duty earthmoving equipment. Strongly cemented zones are likely to be encountered within the Santiago Formation which would entail heavy ripping or the use of rock breaking equipment. 5.4. Groundwater Groundwater was not encountered during drilling along Crest Drive or Monroe Street. Fluc- tuations in the groundwater level and perched conditions may occur due to variations in ground surface topography, subsurface stratification, rainfall, irrigation practices, and other factors that may not have been evident at the time of our field evaluation. 5.5. Faulting and Seismicity The project area is considered to be seismically active. Based on our review of the referenced geo- logic maps and stereoscopic aerial photogr^hs, as well as on our geologic field mapping, the subject site is not underlain by known active or potentially active faults (i.e., faults that exhibit evi- dence of ground displacement in the last 11,000 years and 2,000,000 years, respectively). 106332001 RCicsidoc Crest Drive Storm Drain June 30, 2008 Carlsbad, Califomia Project No. 106332001 pi m m te p te P te In general, hazards associated with seismic activity include; strong ground motion, ground surface mpture, liquefaction, seismically induced settlement, and tsunamis. These hazards are discussed in the following sections. 5.5.L Liquefaction and Seismically Induced Settlement Liquefaction of cohesionless soils can be caused by strong vibratory motion due to earthquakes. Research and historical data indicate that loose granular soils and non- plastic silts that are saturated by a relatively shallow groundwater table are susceptible to liquefaction. Based on the relatively dense nature of the materials imderlying the ahgn- ment and lack of shallow groundwater, the potential for liquefaction and seismically induced settlement is not a design consideration. 5.6. Landsliding Based on our review of published geologic literature and aerial photographs, our geologic reconnaissance, and our subsurface evaluation, no landslides or related features underlie or are adjacent to the subject alignment. 6. CONCLUSIONS Based on the results of our geotechnical evaluation, the proposed constmction of the 18-inch storm drain is feasible from a geotechnical standpoint provided the recommendations presented in this report are incorporated into the design and constmction of the subject project. Geotechni- cal considerations include the following • In general, excavation of the material along the alignment should be achievable with heavy earthmoving equipment in good operating condition. The excavated material is anticipated to be suitable for re-use as backfill provided it is moisture conditioned to near optimum moisture content. Some material types, such as clayey deposits or soils containing oversize cobbles, will not be suitable for placement adjacent to the pipeline. Variations in moisture content will be encountered that will necessitate aeration or moisture conditioning during compaction. • Portions of the storm drain ahgnment are underlain by materials of the Santiago Formation. Strongly cemented zones are likely to be encountered within the Santiago Formation which would entail heavy ripping or the use of rock breaking equipment. P 106332001 RCrcsldoc ^ ^iit^O ^ ^^^XWC^ Crest Drive Storm Drain June 30, 2008 Carlsbad, Califomia Project No. 106332001 Based on our review of published geologic maps, there are no known active faults transect- ing the proposed storm drain alignment. The project site would not be considered corrosive based upon Caltrans criteria. 7. RECOMMENDATIONS The following sections include our geotechnical recommendations for constmction of the pro- posed storm drain. These recommendations are based on our evaluation of the site geotechnical conditions and our understanding of the planned constmction. The proposed improvements should also be performed in accordance with the specifications and requirements of applicable goveming agencies. In the event of conflicting earthwork specifications, we recommend that the more stringent requirements are followed. 7.L Pre-CoDstructioD Conference and Health and Safety Plan We recommend that a pre-constmction conference be held. The owner and/or their represen- tative, the goveming agencies' representatives, the civil engineer, the geotechnical engineer, and the contractor should be in attendance to discuss the work plan, project schedule, earth- work, and shoring requirements. As with constmction projects of this nature, we recommend that work be conducted under the conditions of a Site Specific Health and Safety Plan prepared by a Certified Industrial Hygienist. We also recommend that a monitoring and contingency plan be in place and im- plemented if contamination is encountered during constmction based on the presence of undocumented fill materials. Constmction of proposed improvements should be performed by qualified contractors utilizing appropriate techniques and constmction materials. p 7.2, Excavation Characteristics te Based on our field exploration and experience, we anticipate that excavations within the mate- P rials along the storm drain alignment may be accompHshed with a backhoe, excavator, or other trenching equipment in good condition. However, strongly cemented zones are likely to be en-P 106332001 RCrest.doc yyy/nyi7&yy^QQre Crest Drive Storm Drain June 30, 2008 Carlsbad, Califomia Project No. 106332001 coimtered within the Santiago Formation which would entail heavy ripping or the use of rock m breaking equipment. 7.3. Temporary Excavations, Braced Excavations and Shoring ^ We recommend that trenches and excavations be designed and constmcted in accordance with Occupational Safety and Health Administration (OSHA) regulations. These regulations ^ provide trench sloping and shoring design parameters for trenches up to 20 feet deep based on the soil types encoimtered. Trenches over 20 feet deep should be designed by the Con- ^ tractor's engineer based on site-specific geotechnical analyses. For planning purposes, we ^ recommend that the following OSHA soil classifications be used: Fill Type C Old Paralic Deposits/Santiago Formation Type B p te Upon making the excavations, the soil/rock classifications and excavation performance " should be evaluated in the field by Ninyo & Moore in accordance with OSHA regulations. ^ Temporary excavations should be constmcted in accordance with OSHA recommendations. ^ For trench or other excavations, OSHA requirements regarding personnel safety should be met ^ by using appropriate shoring (mcludmg trench boxes) or by laying back the slopes no steeper than 1.5:1 (horizontal:vertical) in fill and 1:1 in old parahc deposits or Santiago Formation, pa Temporary excavations that encounter seepage may need shoring or may be stabilized by plac- ing sandbags or gravel along the base of the seepage zone. Excavations encountering seepage m should be evaluated on a case-by-case basis. As an altemative to laying back the side walls, te • the excavations may be shored or braced. Temporary earth retaining systems will be subjected p to lateral loads resulting fi-om earth pressures. Figure 4 presents earth pressure diagrams for design of shoring systems for trench and access shaft excavations. F ^ The design of the earth pressure diagram assumes that spoils from the excavation or other F surcharge loads will not be placed above the excavation within a 1:1 plane extending up and IH back from the excavation. If spoil piles are placed closer than this to the braced excavation, the resulting surcharge loads should be considered in the bracing design. In addition. m k p te 106332001 RCresl doc ^//K^^&yyVoore Crest Drive Storm Drain June 30, 2008 Carlsbad. Califomia Project No. 106332001 ^ groundwater pressures and hydrostatic uplift pressures at the base of the excavations should be considered in shoring design. We anticipate that settlement of the ground surface will occur behind the shoring wall during ex- (P. cavation. The amount of settlement depends heavily on the type of shoring system, the shoring ^ contractor's workmanship, and soil conditions. We recommend that stmctures/improvements in m the vicinity of the planned shoring installation be reviewed with regard to foundation support and tolerance to settlement. To reduce the potential for distress to adjacent improvements, we m recommend that the shoring system be designed to reduce the ground settlement behind the shoring system to Vt inch or less. Possible causes of settlement that should be addressed mclude ^ settlement during shoring installation, excavations, constmction vibrations, dewatering, and re- moval of the support system. ^ The contractor should retain a qualified and experienced engineer to design the shoring sys- ^ tem, evaluate the adequacy of these parameters and provide modifications for the design. ^ Shoring plans should be reviewed by the district design engineer. We recommend that the ^ contractor take appropriate measures to protect workers. OSHA requirements pertaining to worker safety should be observed. 7.4. Micro-Tunneling/Jack-and-Bore pi Design of shaft shapes, dimensions, and ground support systems for micro-tunneling/jack- and-bore excavations will be at the contractor's option in order to be compatible with the se- m lected constmction equipment and method. Soldier piles with lagging or shored excavations • may serve as a suitable support system for rectangular shafts but may be difficutt to con- P stmct in cobbly materials, while circular steel ribs in conjunction with timber lagging or te liner plates may be suitable for circular shafts. c c Medium dense granular fill and medium dense to very dense silty sand and is anticipated at the proposed elevations of the proposed jack-and-bore segment of the pipeline. The contractor should take appropriate measures to reduce the loss of material at the casing head. We recom- mend that an experienced specialty contractor be used for the jack-and-bore operations. 106332001 RCrcsl.doc yyy/ry/7&yyVQQre Crest Drive Storm Drain Carlsbad, Califomia June 30, 2008 Project No. 106332001 P m te Ground surface settlements may occur fi-om the pipe jacking operations. However, due to the depth of the proposed pipeline, these settlements are not anticipated to impact surface im- provements and underground utilities, provided an experienced contractor performs the work. In order to evaluate the load factors on the proposed pipeline, the loading presented in the following table should be used. Table 1 - Loading on Jack-and-Bore Segment of Pipeline Approximate Depth from Existing Ground Surface to Top of Pipeline (feet) Load on Pipeline (pounds/lineal foot of pipe) 5 1100 10 1880 15 2,190 20 2,500 25 2,700 Notes: Linear interpolation may be used to obtain loading between the depths shown. Loading assumes 36-inch sleeve diameter of iack-and-bore section. Loading may need to be modified for different sleeve sizes. p k F te m P te Jacking reaction force is developed by the action of the micro-tunneling/jack-and-bore operation against the surface of the opposite wall of the jacking pit. The jackmg force is resisted by the bearing of the wall. The allowable jacking force may be calculated usmg the lateral earth pres- sures shown on Figure 5. These earth pressures are applicable to fill and formational materials. Caving of the pipe shaft may occur, particularly in the fill soils. For stability and safety pur- poses, and to reduce ground movements, a full perimeter shaft support system should be installed as the excavation progresses. 7.5. Excavation Bottom Stability In general, we anticipate that the bottom of the drain pipe trenches will be stable and should provide suitable support to the proposed storm drain. If encountered, particularly in fill ma- terials on Momoe Street, unstable bottom conditions may be mitigated by overexcavating the excavation bottom to suitable depths and replacing with gravel as described herein. Rec- 106332001 R Crest doc Crest Drive Storm Drain June 30, 2008 Carlsbad, Cahfomia Project No. 106332001 ommendations for stabilizing excavation bottoms should be based on evaluation in the field by the geotechnical consultant at the time of constmction. 7.6. Modulus of Soil Reaction The modulus of soil reaction is used to characterize the stif&iess of soil backfill placed at the sides of buried flexible pipelines for the purpose of evaluating deflection caused by the weight of the backfill above the pipe. For pipelines constmcted in granular fill, old parahc deposits, and the Santiago Formation, and backfilled as recommended herein, we recommend that a modulus of soil reaction of 2,000 pounds per square inch (psi) be used for design, provided that granular bedding material is placed adjacent to the pipe, as recommended in this report. 7.7. Pipe Bedding We recommend that pipes be supported on 6 inches or more of granular bedding material such PK as sand with a sand equivalent (SE) value of 30 or more. Bedding material should be placed ^ around the pipe and 12 inches or more above the top of the pipe in accordance with the recent edition of the Standard Specifications for Public Works Constmction ("Greenbook"). We do ^ not recommend the use of cmshed rock as bedding material. It has been our experience that the voids within a cmshed rock material are sufficiently large to allow fines to migrate into the ^ voids, thereby creating the potential for sinkholes and depressions to develop at the ground ^ surface, as well as piping. Where wet and loose or soft soil conditions are encountered, the trench excavation should be extended to approximately 1 foot or more below the pipe invert * elevation and should be backfilled with gravel wrapped in filter fabric, te P P P P k Special care should be taken not to allow voids beneath and around the pipe. Compaction of ite the bedding material and backfill should proceed up both sides of the pipe. Trench backfill, in- cluding bedding material, should be placed in accordance with the recommendations presented li in this report for trench backfill. As a result, we do not recommend that soils generated from the trench excavations be used as bedding material. 10633200T RCrcsldoc 10 yyy/R^i7&yyVQore •M IP te F Crest Drive Storm Drain June 30, 2008 Carlsbad, Califomia Project No. 106332001 7.8. Trench Backflll Trench backfill and stmcture backfill should consist of granular soil with low expansion po- tential that generally conforms to the latest edition of the Standard Specifications for Public Works Constmction ("Greenbook") for stmcture backfill. In general, the on-site sandy soils are considered suitable for re-use as stmctural fill material. Fill material should be granular soil and should be free of trash, debris, roots, vegetation, or deleterious materials. Fill should generally be free of rocks or hard lumps of material in excess of 3 inches in diameter. Rocks or hard lumps larger than about 3 inches in diameter should be broken into smaller pieces or should be removed from the site. Wet materials generated from on-site excavations should be aerated to a moisture content near the laboratory optimum to allow compaction or exported. On-site clayey and organic soils encountered during excavation should be selectively removed and stockpiled separately. The clayey and organic soils are not considered suitable as stmctural fill and should be disposed off site. Unsuitable soils include materials classified as CL, OL, CH, MH, OH, and PT in accordance with the Unified Soil Classification System (USCS). Imported materials should consist of clean, granular materials. The corrosion potential of proposed imported soils should also be evaluated if stmctures will be in contact with the im- ported soils. Import material should be submitted to the geotechnical consultant for review prior to importing to the site. The contractor should be responsible for the uniformity of im- port material brought to the site. 7.9. Backnil Placement and Compaction Stmcture backfill and trench backfill should be placed and compacted in uniform horizontal P lifts to a relative compaction of 90 percent or more as evaluated by the latest edition of Ameri- i can Society for Testing and Materials (ASTM) D 1557. Aggregate base beneath pavement p areas should be compacted to a relative compaction of 95 percent or more. Backfill soils II should be placed at or above the laboratory optimum moisture content as evaluated by the lat- P te est edition of ASTM D 1557. The optimum lift thickness of backfill will depend on the type of compaction equipment used, but generally 8 inches in loose thickness should be used for plan- ^ 106332001 RCresidoc | ^ ^iit^O^^^VX^ Crest Drive Storm Drain June 30, 2008 Carlsbad, Califomia Project No. 106332001 ning. Special care should be taken to avoid pipe damage when compacting trench backfill above the pipe. 7.10. Corrosion ^ Laboratory testing was perfonned on a sample of the on-site materials to evaluate soil pH, electri- cal resistivity, water-soluble chloride content, and water-soluble sulfate content. The soil pH and ^ electrical resistivity tests were performed in general accordance with Califomia Test Method 643. Sulfate and chloride content tests were perfonned in general accordance with Califomia Test ^ Method 417 and 422, respectively. The laboratory test results are presented in Appendix C. pi IH P te The value of soil pH for the tested soil sample is 6.0. The electrical resistivity measured in the laboratory is 1,540 ohm-centimeters. The chloride content of the soil sample is 330 parts per million (ppm) and the sulfate content is 0.002 percent (i.e. 20 ppm). Based on the Caltrans cor- rosion criteria (2006), the on-site soils would not be classified as corrosive, which is defined as soils with more than 500 ppm chlorides, more than 0.2 percent sulfates, or a pH less than 5.5. f*i Due to the potential variability of soils, we recommend that corrosion protection for im- provements in contact with site soils be designed by a corrosion engineer. The water-soluble m sulfate content test results are addressed in the following section of this report, te ^ 7.11. Concrete p Concrete in contact with soil or water that contains high concentrations of water-soluble sulfates F can be subject to premature chemical and/or physical deterioration. The soil samples tested in this evaluation indicated a water-soluble sulfate content of 0.002 percent by weight (i.e., about 20 ppm). Based on the American Concrete Institute (ACI) criteria (2005), the potential for sulfate attack is neghgible for water-soluble sulfate contents in soils ranging from about 0.0 to 0.10 percent by weight (0 to 1,000 ppm) and Type II cement may be used for concrete constmc- tion. However, due to the potential variabihty of site soils, consideration should be given to using Type V cement and concrete with a water-cement ratio no higher than 0.50 by weight for normal weight aggregate concrete and a 28-day compressive strength of4,000 psi or more for the project. c PI te P» te li r te 106332001 RCiKtdoc 12 ^/ry0&yy\Qiire te P te Crest Drive Storm Drain June 30, 2008 Carlsbad, Cahfomia Project No. 106332001 7.12. Pavement Reconstruction Trenching within the street right-of-way will result in the replacement of pavements for the pro- ject. In general, pavement repair should confonn to the material thickness and compaction requirements of the adjacent pavement section. Aggregate base material and asphalt concrete should be compacted to a relative compaction of 95 percent or more in accordance with the latest edition of ASTM D 1557. Actual pavement reconstmction should conform to the requirements of the city/agency of jurisdiction. Additional recommendations may be provided upon request. *• 8. CONSTRUCTION OBSERVATION m The recommendations provided in this report are based on our understanding of the proposed pro- ject and on our evaluation of the data collected based on subsurface conditions observed in widely spaced exploratory borings. It is imperative that the geotechnical consultant checks the subsurface conditions during constmction. We recommend that Ninyo & Moore review the project plans and specifications prior to constmction. It should be noted that, upon review of these documents, some recommendations presented in this report may be revised or modified. During constmction we rec- ommend that the duties of the geotechnical consultant include, but not be limited to: • Observing clearing, gmbbing, and removals. • Observing excavation, placement, and compaction of backfill. • Evaluating imported materials prior to their use as backfill (if used). • Performing field tests to evaluate backfill compaction. P te • Performing material testing services, including concrete compressive strength tests and in- spections. F te • The recommendations provided in this report are based on the assumption that Ninyo & Moore will E provide geotechnical observation and testing services during constmction. In the event that it is de- cided not to utilize the services of Ninyo & Moore during constmction, we request that the selected P consultant provide the client with a letter (with a copy to Ninyo & Moore) indicating that they fully k m m 106332001 R Crcsi doc 13 m te P il [ F te P te P te Crest Drive Storm Drain June 30, 2008 Carisbad, Califomia Project No. 106332001 understand Ninyo & Moore's recommendations, and that they are in full agreement with the design parameters and recommendations presented in this report. ^ 9. LIMITATIONS te The field evaluation, laboratory testing, and geotechnical analyses presented in this geotechnical p report have been conducted in general accordance with current practice and the standard of care te exercised by geotechnical consultants performing similar tasks in the project area. No warranty, fm expressed or implied, is made regarding the conclusions, recommendations, and opinions pre- te sented in this report. There is no evaluation detailed enough to reveal every subsurface condition. m Variations may exist and conditions not observed or described in this report may be encountered ^ during constmction. Uncertainties relative to subsurface conditions can be reduced through addi- m tional subsurface exploration. Additional subsurface evaluation will be performed upon request. *• Please also note that our evaluation was limited to assessment of the geotechnical aspects of the pi project, and did not include evaluation of structural issues, environmental concems, or the pres- ence of hazardous materials. ^ This document is intended to be used only in its entirety. No portion of the document, by itself, is ^ designed to completely represent any aspect of the project described herein. Ninyo & Moore ^ should be contacted if the reader requires additional information or has questions regarding the content, interpretations presented, or completeness of this document. This report is intended for design purposes only. It does not provide sufficient data to prepare an accurate bid by contractors. It is suggested that the bidders and then geotechnical consultant per- form an independent evaluation of the subsurface conditions in the project areas. The independent evaluations may include, but not be limited to, review of other geotechnical reports prepared for the adjacent areas, site reconnaissance, and additional exploration and laboratory testing. Our conclusions, recommendations, and opinions are based on an analysis of the observed site p conditions. If geotechnical conditions different from those described in this report are encountered, k ™ our office should be notified, and additional recommendations, if warranted, will be provided upon 106332001 RCrcsl.doc 14 yy!//^/7&yyvQQre te p PI te PI te P k Crest Drive Storm Drain June 30, 2008 Carlsbad, Califomia Project No. 106332001 request. It should be understood that the conditions of a site could change with time as a result of natural processes or the activities of man at the subject site or nearby sites. In addition, changes to the applicable laws, regulations, codes, and standards of practice may occur due to government ac- tion or the broadening of knowledge. The findings of this report may, therefore, be invalidated over time, in part or in whole, by changes over which Ninyo & Moore has no control. pn This report is intended exclusively for use by tiie client. Any use or reuse of the findings, conclu- te sions, and/or recommendations of this report by parties other than the client is undertaken at said p parties' sole risk, te p te p te p te F li p L r Pl 106332001 R Crcst doc j ^ te Crest Drive Storm Drain Carlsbad, Califomia June 30, 2008 Project No. 106332001 P k m te P k 10. SELECTED REFERENCES American Concrete histittite (ACI), 2005, ACI 318-05 Building Code Requirements for Stmc- tural Concrete and Commentary. Califomia Building Standards Commission (CBSC), 2007, Califomia Building Code (CBC), Ti- tie 24, Part 2, Volumes 1 and 2. Cahfomia Department of Conservation Division of Mines and Geology, 1998, Maps of Known Ac- tive Fault Near-Source Zones in Califomia and Adjacent Portions of Nevada: dated Febmary. Cahfomia Department of Transportation (Caltrans), 2006, Corrosion Guidelines (Version 1.0), Divi- sion of Engineering and Testing Services, Corrosion Technology Branch: dated September. Intemational Conference of Buildmg Ofiicials, 1997, Uniform Building Code (UBC). Jennings, C.W., 1994, Fault Activity Map of Califomia and Adjacent Areas: Califomia Division of Mines and Geology, Califomia Geologic Data Map Series, Map No. 6, Scale 1:750,000. Noms, R. M. and Webb, R. W, 1990, Geology of California, Second Edition: John Wiley & Sons, Inc. Pubhc Works Standards, hic, 2006, "Greenbook," Standard Specifications for Public Works Constmction. United States Geological Survey/California Geological Survey, 2003, Probabihstic Seismic Haz- ards Assessment Model for Califomia. United States Geological Survey/Califomia Geological Survey, 2004, Preliminary Geologic Map of the Oceanside 30' x 60' Quandrangle, San Diego County, Califomia: a Digital Data- base. United States Geological Survey, 1968 (photo-revised 1975), San Luis Rey Quadrangle, Cahfor- nia, San Diego County, 7.5-Minute Series (Topographic): Scale 1:24.000. AERIAL PHOTOGRAPHS Pi Source Date Flight Numbers Scale te USDA 5/2/53 AXM-14M 20 and 21 1:20,000 te P ite r te 106332001 R Cresl-doc 16 %.30 '*^^>/4$^J '- : 1^ ^ PACKARb>!!L •Ji Jib I <C<i sam Ol;~ « \ v & A L o^Bu \ t 14 r- *» % gang.:]- l\\?J5-g 4 %\ -\>iiE>v ^ \ "%.*T^";''^ ^ tw^mf*^'' i^" A ij^lv^^^^ -^^-W.I%/V$LC4^»^^^ ^ ^ REFERENCE; 2005 THOMAS GUIDE FOR SAN DIEGO COUNTY, STREET GUIDE AND DIRECTORY, 0 2400 4800 APPROXIMATE SCALE IN FEET NOTE: ALL DIMENSIONS, DIRECTIONS AND LOCATIONS ARE APPROXIMATE. Map © Rand McNally, R L.07-S-129 SITE LOCATION MAP FIGURE 1 PROJECT NO. DATE CREST DRIVE STORM DRAIN CARLSBAD, CALIFORNIA FIGURE 1 106332001 6/08 CREST DRIVE STORM DRAIN CARLSBAD, CALIFORNIA FIGURE 1 w % mm mm mm ri ri ti ii ii fi ii ti ii ii LEGEND TD=11.5 APPROXIMATE LOCATION OF EXPLORATORY BORING TD=TOTAL DEPTH IN FEET Qaf FILL Qop OLD PARALIC DEPOSITS Tsa SANTIAGO FORMATION APPROXIMATE LOCATION OF GEOLOGIC CONTACT QUERRIED WHERE QUESTIONABLE NOTE. ALL DIMENSIONS, DIRECTIONS AND LOCATIONS ARE APPROXIMATE. APPROXIMATE SCALE 100 200 FEET SOURCE: CREST DRIVE STORM DRAIN, HARRIS & ASSOCIATES, GEOTECHNICAL MAP FIGURE 2 PROJECT NO. DATE CREST DRIVE STORM DRAIN CARLSBAD, CALIFORNIA FIGURE 2 106332001 6/08 CREST DRIVE STORM DRAIN CARLSBAD, CALIFORNIA FIGURE 2 1,1990 FAULT LOCATION MAP FIGURE 3 PROJECT NO. DATE CREST DRIVE STORM DRAIN CARLSBAD, CALIFORNIA FIGURE 3 106332001 6/08 CREST DRIVE STORM DRAIN CARLSBAD, CALIFORNIA FIGURE 3 pi te m te p te In IB u ID GROUND SURFACE SHORING NOTES: 1. APPARENT LATERAL EARTH PRESSURES. Pg ^ AND ^ Pa^ = 2-lHpsf Pa2= 12Hpsf 2. CONSTRUCTION TRAFFIC INDUCED SURCHARGE PRESSURE, Pj Ps = 120 psi 3. WATER PRESSURE, P^^ 62.4 pst 4. PASSIVE PRESSURE. P Pp - 400 D psf 5. SURCHARGES FROM EXCAVATED SOIL OR CONSTRUCTION MATERIALS ARE NOT INCLUDED 6. H, , h2 AND D ARE !N FEET 7. • GROUNDWATER TABLE mi TO SCALE LATERAL EARTH PRESSURES FOR BRACED EXCAVATION BELOW GROUNDWATER FIGURE 4 PROJECT NO. DATE CREST DRIVE STORM DRAIN CARLSBAD, CALIFORNIA FIGURE 4 106332001 6/08 CREST DRIVE STORM DRAIN CARLSBAD, CALIFORNIA FIGURE 4 m te P te to GROUND SURFACE THRUST BLOCK WOr TO SCALE d (VARIES) D (VARIES) P2 NOTES: GROUNDWATER BELOW BLOCK Pp=400(DV) lb/ft GROUNDWATER ABOVE BLOCK N/A ASSUMES BACKFILL iS GRANULAR MATERIAL ASSUMES THRUST BLOCK IS ADJACENT TO COMPETENT MATERIAL D, dANDhARE IN FEET GROUNDWATER TABLE THRUST BLOCK LATERAL EARTH PRESSURE DIAGRAM FIGURE 5 PROJECT NO. DATE CREST DRIVE STORM DRAIN CARLSBAD, CALIFORNIA FIGURE 5 106332001 6/08 CREST DRIVE STORM DRAIN CARLSBAD, CALIFORNIA FIGURE 5 Crest Drive Storm Drain June 30, 2008 Carlsbad, Califomia Project No. 106332001 APPENDIX A BORING LOGS Field Procedure for the Collection of Disturbed Samples ^ Disturbed soil samples were obtained in the field using the following methods. Bulk Samples Bulk samples of representative earth materials were obtained from the exploratory excava- m lions. The samples were bagged and transported to the laboratory for testing. The Standard Penetratiou Test (SPT) Spoon M Disturbed drive samples of earth materials were obtained by means of a Standard Penetration Test spoon sampler. The sampler is composed of a split barrel with an external diameter of P 2 inches and an unlined internal diameter of 1-3/8 inches. The spoon was driven into the te ground 12 to 18 inches with a 140-pound hammer fi"ee-failing from a height of 30 inches in general accordance with ASTM D 1586-99. The blow counts were recorded for every 6 inches • of penetration; the blow counts reported on the logs are those for the last 12 inches of penetra- m tion. Soil samples were observed and removed from the spoon, bagged, sealed and transported to the laboratory for testing. P Field Procedure for the Collection of Relatively Undisturbed Samples m Relatively undisturbed soil samples were obtained in the field using the following method, te The Modified Split-Barrel Drive Sampler p The sampler, with an external diameter of 3.0 inches, was lined with 1-inch long, thin brass rings with inside diameters of approximately 2.4 inches. The sample barrel was driven into the ground with the weight of a 140-pound hammer, in general accordance with ASTM p D 3550-84. The driving weight was permitted to fall freely. The approximate length of the p fall, the weight of the hammer, and the number of blows per foot of driving are presented on the boring logs as an index to the relative resistance of the materials sampled. The samples pi were removed from the sample barrel in the brass rings, sealed, and transported to the labo- te ratory for testing. P M m te p P te ^ 106332001 RCrcsldoc ^ a; > C o o o BORING LOG EXPLANATION SHEET I !0 xx/xx 9 Bulk sample. Modified splil-barrel drive sampler. No recovery with modified splil-barrel drive sampler. Sample relained by others. Standard Penetration Test {SPT), No recovery with a SPT. Shelby lube sample. Distance pushed in inches/length of sample recovered in inches. No recovery with Shelby tube sampler. Continuous Push Sample. Seepage. Groundwater encountered during drilling. Groundwater measured after drilling. SM ALLUVIUM: Solid line denotes unit change. 15 Dashed line denotes material change. Attitudes: Strike/Dip b: Bedding c: Contact j: Joint f Fracture F: Fault cs: Clay Seam s: Shear bss: Basa! Slide Surface sf Shear Fracture sz: Shear Zone sbs: Sheared Bedding Surface JIL The total depth line is a solid line that is drawn at the bottom of the boring. BORING LOG EXPLANATION OF BORrNG LOG SYMBOLS PROJECT NO. DATE Rev, 01/03 FIGURE m te IP IM m m te pi h m te P» Ito U.S.C.S. METHOD OF SOIL CLASSIFICATION MAJOR DIVISIONS SYMBOL TYPICAL NAMES d O Q UJ O UJ < o u o A J — O O UJ o fN I 2 GR.AVELS (More than 1/2 of coarse fraction > No. 4 sieve size) SANDS (More than 1/2 of coarse fraction <No. 4 sieve size) SILTS & CLAYS Liquid Limit <50 SILTS & CLAYS Liquid Limit >50 HIGHLY ORGANIC SOILS GW GP sw Well graded gravels or gravel-sand mixtures, little or no fines Poorly graded gravels or gravel-sand mixtures, little or no fines GM Silty gravels, gravel-sand-siii mixtures GC Clayey gravels, gravel-sand-ciay mixtures SP SM Silty sands, sand-silt mixtures SC Clayey sands, sand-clay mixtures ML CL OL MH : OH Well graded sands or gravelly sands, little or no fines Poorly graded sands or gravelly sands, Mtlle or no fines inorganic silts and very fine sands, rock Hour, silty or clayey line sands or clayey silts with Inorganic clays of low to medium plasticity, gravelly clays, sandy clays, silty clays, lean Organic silts and organic silty clays of low plasticity Inorganic silts, micaceous or diatomaceous fine sandy or silly soils, elastic silts CH Inorganic clays of high plasticity, fat clays Organic clays of medium fo high plasticity, organic silty clays, organic silts Pt Peat and other highly organic soils GRAIN SIZE CHART CLASSIFICATION RANGE OF GRAIN SIZE CLASSIFICATION U S. Standard Sieve Size Griiin Size in Millimelers BOULDERS Above 12" Above 305 COBBLES 12" It) 3" 305 10 76.2 GRAVEL Coarse Fine 3" lo No 4 r 10 3/4" 3'4" to No 4 76 2 to 4 76 76 2 10 19 1 19 1 10 4 76 SAN[> Coarse Medium Fine No 4 10 No 200 No 4 to No 10 No 10 to No 40 No 40 10 No 200 J 76 to 0 075 4 76 10 2 00 2 00 lo0 420 0.420 to 0.075 SILT& CLAY Below No 200 Below 0 075 PLASTICm CHART n 20 30 40 50 BO 70 BD BO WO LIQIIIO LIMIT(LL). •/„ U.S.C.S. METHOD OF SOIL CLASSIFICATION te USCS Soil Clo^siricaiioh Updaled Nov ZOO-J l-o o i CD LU a: o o CO UJ D > D yd o DATE DRILLED 6/6/08 BORING NO. B-l GROUND ELEVATION I85'±(MSL) SHEET OF METHOD OF DRILLING 8" Hollow-Stem Auger DRIVE WEIGHT SAMPLED BY MAH LOGGED BY MAH REVIEWED BY 140 lbs. (Auto-Trip) DROP 30" R] DESCRIPTION/INTERPRETATION I 10 53 7.9 109.2 88/10" 8.6 113.1 SM OLD PARALIC DEPOSITS: (Formerly Terrace Deposits) Reddish brown, damp, medium dense, silty SAND; many roots and organic debris. Dense; fine sand; slightly clayey. Very dense. Total Depth - 10.8 feet. No groundwater encountered. Backfilled with bentonite grout on 6/6/08. Note: Groundwater, though not encoimtered at the time of drilling, may rise lo a higher level due to seasonal variations in precipitation and several other factors as discussed in the report. 15 BORING LOG CREST DRIVE STORM DRAIN CARLSBAD, CALIFORNIA PROJECT NO. 106332001 DATE 6/08 FIGURE A-1 CL LU H CO O O (O Q >- Q: o CQ >- CO o < CO o DATE DRILLED 6/6/08 BORING NO. B-2 GROUND ELEVATION 185'± (MSL) SHEET OF METHOD OF DRILLING 8" Hollow-Stem Auger DRIVE WEIGHT 140 lbs. (Auto-Trip) DROP SAMPLED BY MAH LOGGED BY MAH REVIEWED BY DESCRIPTION/INTERPRETATION 30" RI 80/12" 10 I 80 6.8 120.3 15 I 88/11' 7,1 116,0 _2Q. SM OLD PARALIC DEPOSITS: (Formerly Terrace Deposits) Reddish brown, damp, medium dense, silty fine SAND. Very dense. Trace organics. Trace mica. BORING LOG CREST DRIVE STORM DRAIN CARLSBAD, CALIFORNIA PROJECT NO. 106332001 DATE 6/08 FIGURE A-2 CO LU < CO t-Q. LU G o o Li_ o -J m m a. O Li. o CO Z lU Q >-Q: a o CO >- CO o < CO yd o DATE DRILLED 6/6/08 BORING NO. B-2 GROUND ELEVATION 185'±(MSL) SHEET OF METHOD OF DRILLING 8" Hollow-Stem Auger DRIVE WEIGHT SAMPLED BY MAH LOGGED BY MAH REVIEWED BY 140 lbs. (Auto-Trip) DROP 30" RI DESCRIPTION/INTERPRETATION "IT 85/1 r 4.5 25 1 81 30 56 35 73/10" 107,1 SM OLD PARALIC DEPOSITS: (Formerly Terrace Deposhs) (Continued) Light reddish brown, damp, very dense, silty fine SAND. Very difficult drilling; added water. Trace coarse sand. Light reddish brown to yellowish brown; damp to moist; fine sand; very thmly laminated; little mica. BORING LOG CREST DRIVE STORM DRAIN CARLSBAD, CALIFORNIA PROJECT NO- I06332001 DATE 6/08 FIGURE A-3 CO LU _J •L < CO 03 1-o o CD LU (O o U- o CL CO lU o >- OL a o m >- CO z o i- . < CO yd y=co CO to ^ DATE DRILLED 6/6/08 BORING NO. B-2 GROUND ELEVATION 185'±(MSL) SHEET OF METHOD OF DRILLING 8" Hollow-Stem Auger DRIVE WEIGHT 140 lbs. (Auto-Trip) DROP SAMPLED BY MAH LOGGED BY MAH REVIEWED BY DESCRIPTION/INTERPRETATION 30" RI 'W 50/5' 11.2 110.8 45 50/5" 50 "I 50/4" 55 'I 50/3" SM OLD PARALIC DEPOSITS: (Formerly Terrace Deposits) (Continued) Light reddish brown to yellowish brown, damp to moist, very dense, fine SAND; very ^thinly lammated; little mica. SANTIAGO FORMATION: Olive gray, damp, weakly to moderately cemented, silty SANDSTONE. Auger refusal. _6Q. Total Depth - 56 feet. No groundwater encountered. Backfilled with approximately 19.5 cubic feet of bentonite grout on 6/6/08. Note: Groundwater, though not encountered at the time of drilling, may rise to a higher level due to seasonal variations in precipitation and several other factors as discussed in the report. BORING LOG CREST DRIVE STORM DRAIN CARLSBAD, CALIFORNIA PROJECT NO. 10633200I DATE 6/08 FIGURE A-4 CO >: O O LL i o _) CD LU h- co o o CL CO z LU O a: a O CQ >-CO g I- . < CO ^d to ^ o DATE DRILLED 6/6/08 BORING NO. B-3 GROUND ELEVATION 115'±(MSL) SHEET OF METHOD OF DRILLING 8" Hollow-Stem Auger DRIVE WEIGHT 140 lbs. (Auto-Trip) DROP 30" SAMPLED BY MAH LOGGED BY MAH REVIEWED BY DESCRIPTION/INTERPRETATION RI 28 10 I 37 15 _2a. 10.2 116.0 9.0 114.3 SM FILL: Reddish brown, moist, medium dense, silty SAND; little clay. Interlayers of light gray; silty, coarse sand. Total Depth = 11.5 feet. ~~ —— _ — No groundwater encountered. Backfilled with bentonite grout on 6/6/08. Note: Groundwater, though not encountered at the time of drilling, may rise to a higher level due to seasonal variations in precipitation and several other factors as discussed in the report. BORING LOG CREST DRIVE STORM DRAIN CARLSBAD, CALIFORNU PROJECT NO. 106332001 DATE 6/08 FIGURE A-5 Crest Drive Storm Drain June 30, 2008 Carlsbad, Califomia Project No. 106332001 APPENDIX B LABORATORY TESTING Classification Soils were visually and texturally classified in accordance with the Unified Soil Classification System (USCS) in general accordance with ASTM D 2488. Soil classifications are indicated on the logs of the exploratory excavations in Appendix A. In-Place Moisture and Density Tests The moisture content and dry density of relatively undisturbed samples obtained from the ex- ploratory excavations were evaluated in general accordance with ASTM D 2937. The test results are presented on the logs of the exploratory excavations in Appendix A. Gradation Analysis Gradation analysis tests were performed on selected representative soil samples in general accor- dance with ASTM D 422. The grain-size distribution curves are shown on Figures B-1 through B-3. These test results were utilized in evaluating the soil classifications in accordance with the Unified Soil Classification System. Shear Strength Test |g A shear strength test was performed on an undisturbed sample in general accordance with ASTM D 3080 to evaluate the shear strength characteristics of selected material. The sample was inim- dated during shearing to represent adverse field conditions. The results are shown on Figure B-4. P ill k k m m Soil Corrosivity Test A soil pH, and electrical resistivity test was performed on a representative sample in general ac- cordance with Califomia Test (CT) 643. The chloride content of the selected sample was evaluated in general accordance with CT 422. The sulfate content of the selected sample was evaluated in general accordance with CT 417. The test results are presented on Figure B-5. Pi 106332001 RCrest.doc GRAVEL SAND FINES Coarse Fine Coarse Medium Fine SILT CLAY U.S. STANDARD SIEVE NUMBERS 3" 2- 114" 1" '// «" 8 16 30 50 100 200 HYDROMETER X 70.0 UJ 5 60,0 S 50,0 UJ O OC 30 0 UJ Q. GRAIN SIZE IN MILLIMETERS PERFORMED IN GENERAL ACCORDANCE WITH ASTM D 422-63 (02) Symbol Sample Location Depth (ft) Liquid Limit Plastic Limit Plasticity Index D,o D30 Deo c„ Passing No. 200 {%) USCS • B-1 5,0-6.5 ---------17 SM GRADATION TEST RESULTS FIGURE B-1 PROJECT NO. DATE CREST DRIVE STORM DRAIN CARLSBAD. CALIFORNIA FIGURE B-1 106332001 6/08 CREST DRIVE STORM DRAIN CARLSBAD. CALIFORNIA FIGURE B-1 106332001 SIEVE B-1 O 5,0-6,5.lit GRAVEL SAND FINES Coarse Fine Coarse Medium Fine SILT CLAY U S. STANDARD SIEVE NUMBERS 3- 2 1W" r '/.• 54- V * 8 16 30 50 100 200 HYDROMETER •t GRAIN SIZE IN MILLIMETERS Symbol Sample Location Depth (ft) Liquid Limit Plastic Limit Plasticity Index D30 Deo Co Passing No. 200 (%) USCS • B-2 0.0-5.0 -------~ -24 SM PERFORMED IN GENERAL ACCORDANCE WITH ASTM D 422-63 (02) GRADATION TEST RESULTS FIGURE B-2 PROJECT NO. DATE CREST DRIVE STORM DRAIN CARLSBAD, CALIFORNIA FIGURE B-2 106332001 6/08 CREST DRIVE STORM DRAIN CARLSBAD, CALIFORNIA FIGURE B-2 10633200! SEVE B-2 © 0.0-5,0.ik GRAVEL SAND FINES Coarse Fine Coarse Medium Fine SILT CLAY U.S. STANDARD SIEVE NUMBERS 3- 2' VA- 1- Vi- i^- 4 8 16 30 50 100 200 HYDROMETER 5 60.0 GRAIN SIZE IN MILLIMETERS Symbol Sample Location Depth (ft) Liquid Limit Plastic Limit Plasticity Index D30 Deo c. passing No. 200 {%) USCS • B-3 0,0-5.0 ---------30 SM PERFORMED IN GENERAL ACCORDANCE WITH ASTM D 422-63 (02) GRADATION TEST RESULTS FIGURE B-3 PROJECT NO. DATE CREST DRIVE STORM DRAIN CARLSBAD, CALIFORNIA FIGURE B-3 106332001 6/08 CREST DRIVE STORM DRAIN CARLSBAD, CALIFORNIA FIGURE B-3 m k tO«332D01 SIEVE 8-3 ® 0.0-5.0.xl( 2000 U- CO w UJ a: 1000 (/> cc X 1" • • - ^ * 1000 NORMAL STRESS (PSF) 2000 Description Symbol Sample Location Depth (ft) Shear Strength Cohesion, c (psf) Friction Angle, ^ (degrees) Soil Type Silty SAND B-2 15.0-16.4 Peak 300 41 SM Silty SAND B-2 15.0-16.4 Peak 300 41 SM Silty SAND - -X - -B-2 15.0-16.4 Ultimate 60 33 SM PERFORMED IN GENERAL ACCORDANCE WITH ASTM D 3080-04 DIRECT SHEAR TEST RESULTS FIGURE B-4 PROJECT NO. DATE CREST DRIVE STORM DRAIN CARLSBAD, CALIFORNIA FIGURE B-4 106332001 6/08 CREST DRIVE STORM DRAIN CARLSBAD, CALIFORNIA FIGURE B-4 106332001 SHEAR B-2iai5D-16.4.xls SAMPLE LOCATION SAMPLE DEPTH (FT) RESISTIVITY (Ohm-cm) SULFATE CONTENT ^ (ppm) 1%) CHLORIDE CONTENT' (ppm) B-2 0.0-5.0 6.0 1,540 20 0.002 330 m p ii ff k PERFORMED IN GENERAL ACCORDANCE WITH CALIFORNIA TEST METHOD 643 PERFORMED IN GENERAL ACCORDANCE WITH CALIFORNIA TEST METHOD 417 PERFORMED IN GENERAL ACCORDANCE WITH CALIFORNIA TEST METHOD 422 CORROSIVITY TEST RESULTS FIGURE B-5 PROJECT NO. DATE CREST DRIVE STORM DRAIN CARLSBAD. CALIFORNIA FIGURE B-5 106332001 6/08 CREST DRIVE STORM DRAIN CARLSBAD. CALIFORNIA FIGURE B-5 li m 106332001 CORROSIVITY Pagel-ids Crest Drive Storm Drain Appendix C Carlsbad, Califomia Project No. 106332001 m ^ APPENDIX C pi TYPICAL EARTHWORK GUIDELINES P P m p il ^1 ii p k P IF= 106332001 TEGdoc Crest Drive Storm Drain Carlsbad, Califomia Appendix C Project No. 106332001 P P m p p ii p in p p p m P TABLE OF CONTENTS Page 1. GENERAL 1 2. OBLIGATIONS OF PARTIES 2 3. SITE PREPARATION 3 4. TRENCH BACKFILL 3 5. SITE PROTECTION 4 6. DEFINITIONS OF TERMS 6 IO63320OI TEG.doc m Crest Drive Storm Drain Appendix C Carisbad, Califomia Project No. 106332001 TYPICAL EARTHWORK GUIDELINES 1. GENERAL These guidelines are presented as general procedures for earthwork construction. They are to be utilized in conjunction with the project plans. These guidelines are considered a part of the geo- technical report, but are superseded by recommendations in the geotechnical report in the case of conflict. Evaluations performed by the consultant during the course of constmction may result in new recommendations which could supersede these specifications and/or the recommendations of the geotechnical report. It is the responsibility of the contractor to read and understand these Guidelines as well as the geotechnical report and project plans. m p 1.1. The contractor shall not vary from these Guidelines without prior recommendations by the geotechnical consultant and the approval of the client or the client's authorized rep- P resentative. Recommendations by the geotechnical consultant and/or client shall not be P considered to preclude requirements for approval by the jurisdictional agency prior to the execution of any changes. Ml M 1-2. The contractor shall perform the earthwork operations in accordance with these speci- fications, and shall be responsible for the quality of the finished product P notwithstanding the fact that earthwork will be observed and tested by the geotechnical P consultant. p 1.3. It is the responsibihty of the contractor to notify the geotechnical consultant and the p jurisdictional agencies, as needed, prior to the start of work at the site and at any time that earthwork resumes after intermption. Each step of the earthwork operations shall P be observed and documented by the geotechnical consultant and, where needed, re- IH viewed by the appropriate jurisdictional agency prior to proceeding with subsequent work. P Il 1.4. If, during the earthwork operations, geotechnical conditions are encountered which were not anticipated or described in the geotechnical report, the geotechnical consult- P ant shall be notified immediately and additional recommendations, if applicable, may il be provided. p 1.5. An as-built geotechnical report shall be prepared by the geotechnical consultant and ii signed by a registered engineer. The report documents the geotechnical consultants' observations, and field and laboratory test results, and provides conclusions regarding P whether or not earthwork constmction was perfonned in accordance with the geotech- il nical recommendations and the plans. 106332001 TEG doc Crest Drive Storm Drain Appendix C Carisbad, California Project No. 106332001 1.6. Definitions of terms utihzed in the remainder of these specifications have been pro- vided in Section 6. 2. OBLIGATIONS OF PARTIES *" The parties involved in the projects earthwork activities shall be responsible as outlined in the IM following sections. mm m 2.1. The client is ultimately responsible for each of the aspects of the project. The client or the client's authorized representative has a responsibility to review the findings and ^ recommendations of the geotechnical consultant. The client shall authorize the contrac- tor and/or other consultants to perform work and/or provide services. During earthwork the client or the client's authorized representative shall remain on site or remain rea- sonably accessible to the concerned parties to make the decisions that may be needed to maintain the flow of the project. 2.2. The contractor is responsible for the safety of the project and satisfactory completion of pipeline installation and other associated operations, including, but not limited to, earthwork in accordance with the project plans, specifications, and jurisdictional * agency requirements. The contractor shall fiirther remain accessible during non- i" working hours times, including at night and during days off * 2.3. The geotechnical consultant shall provide observation and testing services and shall i( make evaluations to advise the client on geotechnical matters. The geotechnical con- sultant shall report findings and recommendations to the client or the client's * authorized representative. m 2.4. Prior to proceeding with any earthwork operations, the geotechnical consultant shall be P notified two working days in advance to schedule the needed observation and test- P ing services. p 2.4.1. Prior to any significant expansion or reduction in the grading operation, the li geotechnical consultant shall be provided with two working days notice to make appropriate adjustments in scheduling of on-site personnel. P P 2.4.2. Between phases of earthwork operations, the geotechnical consultant shall be provided with two working days notice in advance of commencement of ad- P ditional operations. ii p p 106332001 TEG doc P Crest Drive Storm Drain Appendix C Carlsbad, Califomia Project No. 106332001 3. SITE PREPARATION Site preparation shall be performed in accordance with the recommendations presented in the following sections. 3.1. The client, prior to any site preparation or earthwork, shall arrange and attend a pre-constmction meeting between the contractor, the design engineer, the geotechnical consultant, and representatives of appropriate goveming authorities, as well as any other involved parties. The parties shall be given two working days notice. 3.2. Demolition in the areas to be graded shall include removal of pavements, and other manmade surface and subsurface improvements. Demolition of utilities shall include capping or rerouting of pipeHnes at the project perimeter. 3.3. The debris generated during demolition operations shall be removed from areas to be graded and disposed of off site at a legal dump site. Demolition operations shall be per- formed under the observation of the geotechnical consultant. 4. TRENCH BACKFILL m ^ The following sections provide recommendations for backfilling of trenches. • 4.1. Trench backfill shall consist of granular soils (bedding) extending from the trench bot- Hi torn to 1 or more feet above the pipe. On-site or imported fill which has been evaluated by the geotechnical consultant may be used above the granular backfill. The cover soils P directly in contact with the pipe shall be classified as having a very low expansion po- p tential, in accordance with UBC Standard 18-2, and shall contain no rocks or chunks of hard soil larger than 3/4-inch in diameter. m na 4.2. Trench backfill shall, unless otherwise recommended, be compacted by mechanical means to 90 percent relative compaction as evaluated by ASTM D 1557. Backfill soils • shall be placed in loose lifts 8 inches thick or thinner, moisture conditioned, and com- P pacted in accordance with the recommendations of the geotechnical report and of these guidelines. The backfill shall be tested by the geotechnical consultant at vertical inter- vals of approximately 2 feet of backfill placed and at spacings along the trench of fel approximately 100 feet in the same tift. P 4.3. Jetting of trench backfill materials is generally not a recommended method of densifi- P cation, unless the on-site soils are sufficiently free-draining and provisions have been made for adequate dissipation of the water utilized in the jetting process. p 4.4. If it is decided that jetting may be utilized, granular material with a sand equivalent greater than 30 shall be used for backfilling in the areas to be jetted. Jetting shall gener- k 106332001 TEG doc Crest Drive Storm Drain Appendix C Carisbad, Califomia Project No. 106332001 "* ally be considered for trenches 2 feet or narrower in width and 4 feet or shallower in '•' depth. Following jetting operations, french backfill shall be mechanically compacted to the specified compaction to finish grade. 4.5. Trench backfill which underlies the zone of influence of foundations shall be mechani- cally compacted to a relative compaction of 90 percent as evaluated by ASTM D 1557. " The zone of influence of the foundations is generally defined as the roughly triangular area within the limits of a 1:1 (horizontal:vertical) projection from the iimer and outer ^ edges of the foundation, projected down and out from both edges. 4.6. Trench backfill within slab areas shall be compacted by mechanical means to a relative compaction of 90 percent as evaluated by ASTM D 1557. For minor interior trenches, density testing may be omitted or spot testing may be perfonned, as deemed appropri- ate by the geotechnical consultant. *" 4.7. When compacting soil in close proximity to utilities, care shall be taken by the contrac- *• tor so that mechanical methods used to compact the soils do not damage the utilities. * 4.8. Clean granular backfill and/or bedding materials are not recommended for use in slope P areas unless provisions are made for a drainage system to mitigate the potential for buildup of seepage forces or piping of backfill materials. P M 4.9. The contractor shall exercise the specified safety precautions, in accordance with OSHA Trench Safety Regulations, while conducting trenching operations. Such pre- cautions include shoring or laying back trench excavations at 1:1 or flatter, depending P on material type, for trenches in excess of 5 feet in depth. The geotechnical consultant is not responsible for the safety of trench operations or stability of the trenches. ^ 5. SITE PROTECTION H The site shall be protected as outlined in the following sections. J 5.1. Protection of the site during the period of constmction shall be the responsibility of the m k p p p p p m contractor unless other provisions are made in writing and agreed upon among the concerned parties. Completion of a portion of the project shall not be considered to preclude that portion or adjacent areas fix)m the need for site protection, until such time as the project is finished as agreed upon by the geotechnical consultant, the client, and the regulatory agency. 5.2. The contractor is responsible for the stability of temporary excavations. Recommenda- tions by the geotechnical consultant pertaining to temporary excavations are made in consideration of stability of the finished project and, therefore, shall not be considered to preclude the responsibilities of the contractor. Recommendations by the geotechni- 106332001 TEG doc Crest Drive Storm Drain Appendix C Carlsbad, Califomia Project No. 106332001 cal consultant shall also not be considered to preclude more restrictive requirements by the applicable regulatory agencies. 5.3. Precautions shall be taken during the performance of site clearing, excavation, and grading to protect the site from flooding, ponding, or inundation by surface runoff Temporary provisions shall be made during the rainy season so that surface runoff is away fix)m and off the working site. Where low areas cannot be avoided, pumps shall be provided to remove water as appropriate diuing periods of rainfall. 5.4. Following periods of rainfall, the contractor shall contact the geotechnical consultant and arrange a walk-over of the site in order to visually assess rain-related damage. The geotechnical consultant may also recommend excavation and testing in order to aid in the evaluation. At the request of the geotechnical consultant, the contractor shall make excavations in order to aid in evaluation of the extent of rain-related damage. 5.5. Rain- or irrigation-related damage shall be considered to include, but may not be lim- ited to, erosion, silting, saturation, swelling, stmctural distress, and other adverse conditions noted by the geotechnical consultant. Soil adversely affected shall be classi- fied as "Unsuitable Material" and shall be subject to overexcavation and replacement with compacted fill or to other remedial grading as recommended by the geotechnical consultant. P P m p m m m k 106332001 TEG doc Crest Drive Storm Drain Carlsbad, Califomia Appendix C Project No. 106332001 PM P P P ii p 6. DEFINITIONS OF TERMS ALLUVIUM: AS-GRADED (AS-BUILT): BEDROCK: BORROW (IMPORT): CrvIL ENGINEER: CLIENT: COLLUVflJM: COMPACTION: CONTRACTOR: DEBRIS: P P li ENGINEERED FILL: Unconsohdated detrital deposits deposited by flowing water; includes sediments deposited in river beds, canyons, flood plains, lakes, fans at the foot of slopes, and in estuaries. The site conditions upon completion of grading. Relatively undisturbed in-place rock, either at the surface or beneath surficial deposits of soil. Any fill material hauled to the project site from off-site areas. The Registered Civil Engineer or consulting firm responsible for preparation of the grading plans and surveying, and evaluating as-graded topographic conditions. The developer or a project-responsible authorized represen- tative. The client has the responsibility of reviewing the findings and recommendations made by the geotechnical consultant and authorizing the contractor and/or other con- sultants to perfonn work and/or provide services. Generally loose deposits, usually found on the face or near the base of slopes and brought there chiefly by gravity through slow continuous downhill creep (see also Slope Wash). The densification of a fill by mechanical means. A person or company under contract or otherwise retained by the cHent to perform, excavation, pipehne installation, and other site improvements. The products of clearing, gmbbing, and/or demolition, or contaminated soil material unsuitable for reuse as compacted backfill, and/or any other material so designated by the geo- technical consultant. A fill which the geotechnical consultant or the consultant's representative has observed and/or tested during placement, enabling the consultant to conclude that the fill has been placed in substantial comphance with the recommendations of the geotechnical consultant and the goveming agency re- quirements. P P k 106332001 TEG doc Crest Drive Storm Drain Carlsbad, Califomia Appendix C Project No. 106332001 ENGINEERING GEOLOGIST: IP m EROSION: EXCAVATION: EXISTING GRADE: FILL: FINISH GRADE: GEOFABRIC: GEOTECHNICAL CONSULTANT: GEOTECHNICAL ENGINEER: p P p P P k p P GRADING: LANDSLIDE DEPOSITS: A geologist registered by the state hcensing agency who ap- plies geologic knowledge and principles to the exploration and evaluation of naturally occurring rock and soil, as re- lated to the design of civil works. The wearing away of the ground surface as a result of the movement of wind, water, and/or ice. The mechanical removal of earth materials. The ground surface configuration prior to grading; original grade. Any deposit of soil, rock, soil-rock blends, or other similar materials placed by man. The as-graded grotmd surface elevation that conforms to the grading plan. An engineering textile utihzed in geotechnical applications such as subgrade stabilization and filtering. The geotechnical engineering and engineering geology con- sulting firm retained to provide technical services for the project. For the purpose of these specifications, observations by the geotechnical consultant include observations by the geotechnical engineer, engineering geologist and other per- sons employed by and responsible to the geotechnical consuhant. A Hcensed civil engineer and geotechnical engineer, regis- tered by the state licensing agency, who applies scientific methods, engineering principles, and professional experience to the acquisition, interpretation, and use of knowledge of materials of the earth's cmst to the resolution of engineering problems. Geotechnical engineering encompasses many of the engineering aspects of soil mechanics, rock mechanics, geology, geophysics, hydrology, and related sciences. Any operation consisting of excavation, filling, or combina- tions thereof and associated operations. Material, often porous and of low density, produced from instabihty of natural or manmade slopes. 106332001 TEG doc p p p m p p p II p p Crest Drive Storm Drain Carlsbad, Califomia Appendix C Project No. 106332001 OPTIMUM MOISTURE: RELATIVE COMPACTION: SITE: SLOPE WASH: SLOUGH: SOIL: The moisture content that is considered optimum relative to compaction operations. The degree of compaction (expressed as a percentage) of a material as compared to the dry density obtained from ASTM test method D 1557. The particular parcel of land where earthwork is being per- formed. Soil and/or rock material that has been transported down a slope by gravity assisted by the action of water not confined to channels (see also Colluvium). Loose, imcompacted fill material generated during grading operations. Naturally occurring deposits of sand, silt, clay, etc., or com- binations thereof P 1^ 106332001 TEG doc