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Home My WebLink AboutCDP 16-28; ARMY/NAVY STUDENT ENRICHMENT CENTER; PRELIMINARY GEOTECHNICAL INVESTIGATION; 2012-08-06I" CHR-ISTIAN WHEELER- EN G IN E E R- ING REPORT OF PRELIMINARY GEOTECHNICAL INVESTIGATION PROPOSED ATHLETIC FIELD IMPROVEMENTS ARMY NAVY ACADEMY CARLSBAD BOULEVARD CARLSBAD, CALIFORNIA 1.• . I DEC2013 LAND DEVELOP\AEN PREPARED FOR :n . ---.' , - ARMY AND NAVY ACADEMY 2605 CARLSBAD BOULEVARD CARLSBAD, CALIFORNIA 92008 PREPARED BY CHRISTIAN WHEELER ENGINEERING 3980 HOME AVENUE SAN DIEGO, CALIFORNIA 92105 3980 Home Avenue San Diego, CA 92105 • 619-550-1700 • FAX 619-550-1701 [i I" WN Ci-IRiSTIAN WHEELEft ENGINEER.ING August 6, 2012 Army and Navy Academy CWE 2120311.02R 2605 Carlsbad Boulevard Carlsbad, California 92008 Subject: Report of Preliminary Geotechnical Investigation, Proposed Athletic Field Improvements, Army and Navy Academy, Carlsbad, California. Ladies and Gentlemen: In accordance with your request and our proposal dated June'11, 2012, we have completed a preliminary geotechnical investigation for the proposed single-family home to be constructed at the subject property. It is our opinion that no geotechnical conditions exist at the subject property that would preclude the construction of the athletic field improvements as presently proposed. The main geotechnical condition affecting the proposed construction consists of potentially compressible fill and native soils underlying the site to varying depths. This condition is discussed in the attached report. If you have any questions after reviewing this report, please do not hesitate to contact our office. This opportunity to be of professional service is sincerely appreciated. 'F ' * M CERTIFIED -4 ENGINEERING * GEOLOGIST 10-12 EX . Respectfully submitted, CHRISTIAN \ EEL ENGINEERING amel BAd , RC 43603 FEW C arles H.Christi//R CHC:DRR:DBA cc: (2) Addressee kevirihallock@houseanddodge.com Curtis R. Burdelt, eeK~9 3980 Home Avenue San Diego, CA 92105 619-550-1700. FAX 619-550-1701 S TABLE OF CONTENTS Page Introductionand Project Description .............................................................................................................................. 1 Scopeof Services.................................................................................................................................................................2 Findings.................................................................................................................................................................................3 SiteDescription...............................................................................................................................................................3 General, Geology and Subsurface Conditions ...........................................................................................................3 Geologic Setting and Soil Description.....................................................................................................................3 ArtificialFill ............................................................................................................................................................. 3 Topsoil.......................................................................................................................................................................3 OldParalic Deposits...............................................................................................................................................3 Groundwater....................................................................................................................................................... . ........ 4 TectonicSetting...........................................................................................................................................................4 GeologicHazards............................................................................................................................................................5 SlopeStability...............................................................................................................................................................5 Liquefaction.................................................................................................................................................................5 Flooding......................................................................................................................................................................... 5 Tsunamis......................................................................................................................................................................5 Seiches...........................................................................................................................................................................5 Other Potential Geologic Hazards...........................................................................................................................5 Conclusions..........................................................................................................................................................................6 Recommendations................................................................................................................................................................ 6 Gradingand Earthwork ................................................................................................................................................... 6 General..........................................................................................................................................................................6 PregradeMeeting.........................................................................................................................................................6 . Observation of Grading..............................................................................................................................................6 Clearingand Grubbing................................................................................................................................................7 SitePreparation............................................................................................................................................................7 ExcavationCharacteristics ..........................................................................................................................................7 Processingof Fill Areas...............................................................................................................................................7 Compactionand Method of Filling ............................................................................................................................ 8 TemporarySlopes .......................................................................................................................................................8 SurfaceDrainage.........................................................................................................................................................8 GradingPlan Review ................................................................................................................................................... 9 Foundations.....................................................................................................................................................................9 General..........................................................................................................................................................................9 FoundationDimensions ............................................................................................................................................9 BearingCapacity..........................................................................................................................................................9 FootingReinforcement............................................................................................................................................10 LateralLoad Resistance .................................................................. ...................................................... ..................... 10 SeismicDesign Factors ............................................................................................................................................10 ExpansiveCharacteristics ........................................................................................................................................11 SettlementCharacteristics........................................................................................................................................11 FoundationExcavation Observation......................................................................................................................11 FoundationPlan Review..........................................................................................................................................11 SolubleSufates...........................................................................................................................................................12 On-Grade Slabs..............................................................................................................................................................12 General........................................................................................................................................................................12 InteriorFloor Slabs....................................................................................................................................................12 Under-Slab Vapor Retarders.....................................................................................................................................12 ExteriorConcrete Flatwork.....................................................................................................................................13 CWE2120311.02R Proposed Athletic Field Improvements Army and Navy Academy Carlsbad Boulevard Carlsbad, California Earth Retaining Walls .13 Foundations................................................................................................................................................................13 PassivePressure..........................................................................................................................................................13 ActivePressure...........................................................................................................................................................14 Backfill......................................................................................................................................................................... 14 Preliminary Pavement Sections.....................................................................................................................................14 TrafficIndex ........................................................................................... . ................................................................... 14 R-Value Test...............................................................................................................................................................15 PreliminaryPavement Section .................................................................................................................................. 15 Limitations. ...................... . ................................................................................................................................................... 16 Review, Observations and Testing.............................................................................................................................16 Uniformityof Conditions ............................................................................................................................................17 Changein Scope............................................................................................................................................................17 TimeLimitations ...........................................................................................................................................................17 ProfessionalStandara ............................................................................................ . ...................................................... 17 Client's Responsibility...................................................................................................................................................18 FieldExplorations.............................................................................................................................................................18 LaboratoryTesting............................................................................................................................................................19 ATTACHMENTS TABLES Table I Seismic Design Parameters FIGURES Figure 1 Site Vicinity Map, Follows Page 1 PLATES Plate I Site Plan & Geotechnical Map Plates 2-9 Boring Logs Plate 10 Slope Log Plate 11 & 12 Laboratory Test Results Plate 13 Retaining Wall Subdrain APPENDICES Appendix A References Appendix B Recommended Grading Specifications-General Provisions CWE 2120311.02R Proposed Athletic Field Improvements Army and Navy Academy Carlsbad Boulevard Carlsbad, California CHIRJSTIAN WHEELER- EN GIN E E R_ ING PRELIMINARY GEOTECHNICAL INVESTIGATION PROPOSED ATHLETIC FIELD IMPROVEMENTS ARMY AND NAVY ACADEMY CARLSBAD BOULEVARD CARLSBAD, CALIFORNIA INTRODUCTION AND PROJECT DESCRIPTION This report presents the results of a preliminary geotechnical investigation performed for the proposed improvements to the Army and Navy Academy athletic field, located adjacent to and east of Carlsbad Boulevard, in the city of Carlsbad, California. The following Figure Number 1 presents a vicinity map showing the location of the property. We understand that the proposed improvements will consist of an athletic complex building and an is associated parking lot north of the field, a maintenance building and two parking lots south of the field, and a ticket booth, a two-story press box, bleachers, and two dugouts. The athletic building and gym north of the field will be a two-story building of approximately 28,000 square feet. The structure will likely be of concrete tilt-up and wood-frame construction with an on-grade concrete floor slab. The maintenance building south of the field will be a two-story building with storage in the lower floor level. Some retaining walls will be incorporated into the western and southern sides of this building. This structure will likely be of wood-frame construction above grade and masonry construction below grade. It is assumed that grading will consist of cuts and fills of less than about ten feet from existing grades. To aid in the preparation of this report, we were provided with a site plan showing the site configuration and location of the proposed improvements prepared by House & Dodge, dated June 4, 2012. A copy of the plan has been used as the base for our Site Plan and Geotechnical Map, and is included herein as Plate No. 1. This report has been prepared for the exclusive use of the Army and Navy Academy and their design consultants, for specific application to the project described herein. Should the project be modified, the conclusions and recommendations presented in this report should be reviewed by Christian 3980 Home Avenue • San Diego, CA 92105 619-550-1700 • FAX 619-550-1701 Site Vicinity Map PROPOSED ATHLETIC FIELD IMPROVEMENTS ARMY AND NAVY ACADEMY CARLSBAD, CALIFORNIA \\t-[ SITE /I, J 0 0 U 0 0 0 a 0 (\'1 21L1I.2R \LGLST 2t F!GLRF I CWE 2120311.02R August 6, 2012 Page No. 2 Wheeler Engineering for conformance with our recommendations and to determine whether any additional subsurface investigation, laboratory testing and/or recommendations are necessary. Our professional services have been performed, our findings obtained and our recommendations prepared in accordance with generally accepted engineering principles and practices. This warranty is in lieu of all other warranties, expressed or implied. SCOPE OF SERVICES Our preliminary geotechnical investigation consisted of surface reconnaissance, subsurface exploration, obtaining representative soil samples, laboratory testing, analysis of the field and laboratory data, and review of relevant geologic literature. Our scope of service did not include assessment of hazardous substance contamination, recommendations to prevent floor slab moisture intrusion or the formation of mold within the structures, evaluation or design of storm water infiltration facilities, or any other services not specifically described in the scope of services presented below. More specifically, the intent of our investigation was to: Drill eight small-diameter borings in order to explore the subsurface soil conditions and to obtain soil samples for laboratory testing. Evaluate, by laboratory tests and our past experience with similar soil types, the engineering properties of the various strata that may influence the proposed construction, including bearing capacities, expansive characteristics and settlement potential. Describe the general geology at the site including possible geologic hazards that could have an effect on the proposed construction, and provide the seismic design parameters as required by the 2010 edition of the California Building Code. Address potential construction difficulties that may be encountered due to soil conditions, groundwater or geologic hazards, and provide recommendations concerning these problems. Provide site preparation and grading recommendations. Provide foundation recommendations for the type of construction anticipated and develop soil engineering design criteria for the recommended foundation designs. Provide earth retaining wall design criteria. Prepare a preliminary geotechnical investigation report discussing our findings and geotechnical recommendations for the proposed construction. CWE 2120311.02R August 6, 201.2 Page No. 3 S FINDINGS SITE DESCRIPTION The subject site is located adjacent to and east of Carlsbad Boulevard in the city of Carlsbad, and is identified as Assessor's Parcel Numbers 203-051-03, 203-052-01, 203-052-02, and 203-053-01. The main portion of the campus is located west of Carlsbad Boulevard, at 2605 Carlsbad Boulevard. The property is bounded on the west by Carlsbad Boulevard, on the east by a railroad easement, on the south by Beech Avenue and a public building and associated parking lot, and on the north by a commercial building. The site is currently used as the athletic/parade field for the Academy. Existing improvements include two dugouts, bleachers, a scoreboard, and a two-story structure. A brick retaining wall/site wall exists along the western portion of the southern property line. The wall has a maximum height of about four feet, and shows signs of structural distress. GENERAL GEOLOGY AND SUBSURFACE CONDITIONS GEOLOGIC SETTING AND SOIL DESCRIPTION: The subject site is located within the Coastal Plains Physiographic Province of San Diego County. Based on the results of our subsurface explorations, and analysis of readily available, pertinent geologic literature, it was determined that the site is generally underlain by fill, topsoil, and Quaternary-age old paralic (terrace) deposits. These materials are described below: ARTIFICIAL FILL (Qaf): Artificial fill was encountered in boring B-I extending to a depth of about 5½ feet below existing grade. The fill depth may be deeper in areas of the site not investigated. Based on the original site topography, fill materials are anticipated at the northeastern portion of the site. The fill encountered consists of brown to dark brown, damp to moist, loose, silty sands (SM). The fill was judged to have a low Expansion Index (EI<50). TOPSOIL: A thin surficial veneer of topsoil was encountered in borings B-2, B-3, B-4, and B-8, extending to a maximum depth of about two feet below existing grade. The topsoil consists of brown to dark brown, damp to moist, loose to medium dense, silty sands (SM). The topsoil was judged to have a low Expansion Index (EI<50). OLD PARALIC DEPOSITS (Qop): Quaternary-age old paralic (terrace) deposits were encountered underlying the surficial soils. In general, these old paralic deposits consist of CWE 2120311.02R August 6, 2012 Page No. 4 interbedded brown to light reddish-brown and grayish-brown, dry to moist, silty sand (SM), slightly silty, poorly-graded sand (SP-SM), and silty sand with clay (SM), and grayish-brown, moist, sandy clay (CL). The paralic deposits were loose to medium dense and weathered to depths ranging from approximately 2 to 9 feet below existing grades, and medium dense to dense or stiff thereafter. The sandy portions of the old paralic deposits were judged to possess a very low expansion index (EI<20) and the clayey portions were judged to possess a low to moderate expansion index (El between 51 to 90). GROUNDWATER: No groundwater or seepage was encountered in our subsurface explorations. However, it should be recognized that minor groundwater seepage problems might occur after site construction and landscaping are completed, even at sites where none were present before construction. These are usually minor phenomena and are often the result of an alteration in drainage patterns and/or an increase in irrigation water. It is further our opinion that these problems can be most effectively corrected on an individual basis if and when they occur. TECTONIC SETTING: It should be noted that much of Southern California, including the San Diego County area, is characterized by a series of Quaternary-age fault zones that consist of several is individual, en echelon faults that generally strike in a nor:herly to northwesterly direction. Some of these fault zones (and the individual faults within the zone) are classified as active while others are classified as only potentially active according to the criteria of the California Division of Mines and Geology. Active fault zones are those which have shown conclusive evidence of faulting during the Holocene Epoch (the most recent 11,000 years) while potentially active fault zones have demonstrated movement during the Pleistocene Epoch (11,000 to 1.6 million years before the present) but no movement during Holocene time. Inactive faults are those faults that can be demonstrated to have no movement in the past 1.6 million years. No active or potentially active faults have been mapped at or in the vicinity of the subject site. It should be recognized that the active Newport-Inglewcod Fault Zone is located approximately 71/2 kilometers east of the site. Other active fault zones in the region that could possibly affect the site include the Coronado Bank, San Diego Trough, and San Clemente Fault Zones to the southwest; the Earthquake Valley and Palos Verdes Fault Zones to the north; and the Elsinore and San Jacinto Fault Zones to the northeast. 0 CWE 2120311.02R August 6, 2012 Page No. 5 0 GEOLOGIC HAZARDS SLOPE STABILITY: As part of this investigation we reviewed the publication, "Landslide Hazards in the Northern Part of the San Diego Metropolitan Area" by Tan and Giffen, 1995. This reference is a comprehensive study that classifies San Diego County into areas of relative landslide susceptibility. The subject site is located in Area 2, which is considered to be "marginally susceptible" to slope failures. Based on our findings, it is our opinion that the likelihood of slope stability related problems at the site is very low. LIQUEFACTION: The earth materials underlying the site are not considered subject to liquefaction due to such factors as soil density, grain-size distribution, the absence of shallow groundwater conditions. FLOODING: The site is not located within either the 100-year flood zone or the 500-year flood zone. TSUNAMIS: Tsunamis are great sea waves produced by a submarine earthquake or volcanic eruption. Historically, the San Diego area has been free of tsunami-related hazards and tsunamis reaching San Diego have generally been well within the normal tidal range. It is thought that the wide continental margin off the coast acts to diffuse and reflect the wave energy of remotely generated tsunamis. The largest historical tsunami to reach San Diego's coast was 4.6 feet high, generated by the 1960 earthquake in Chile. A lack of knowledge about the offshore fault systems makes it difficult to assess the risk due to locally generated tsunamis. However, the risk associated with tsunamis in the San Diego region is considered to be generally low. Based on the site's location and elevation, the risk potential of tsunamis affecting the subject site is considered negligible. Furthermore, as presented on San Luis Rey Quadrangle of the Tsunami Inundation Map for Emergency Planning (CEMA, 2009), the site is not mapped within a tsunami inundation area. SEICHES: Seiches are periodic oscillations in large bodies of water such as lakes, harbors, bays or reservoirs. Due to the site's location, it is considered to have a negligible risk potential for seiches. OTHER POTENTIAL GEOLOGIC HAZARDS: Other potential geologic hazards such as, volcanoes or seismic-induced settlement should be considered to be negligible or nonexistent. CWE 2120311.02R August 6, 2012 Page No. 6 CONCLUSIONS In general, it is our professional opinion and judgment that, from a geologic and geotechnical perspective, the subject property is suitable for the proposed construction provided the recommendations presented herein are implemented. The site is underlain by potentially compressible fill, topsoil, and weathered old paralic deposits ranging in combined depth from about 1 foot to 9 feet below existing grade. Below said depth the old paralic deposits are medium dense to dense or stiff in consistency. In order to mitigate this condition, it is recommended that the potentially compressible materials be removed and replaced as compacted fill. Some of the old paralic deposits encountered appear to be moderately expansive. However, it is anticipated that these deposits will be several feet below finish pad grade elevations, and will not detrimentally affect the proposed improvements. Other than the potential for seismically induced ground shaking, as described herein, the site should be safe from geologic hazards at the conclusion of constiuction, provided the recommendations contained herein are implemented and sound construction practices are followed. RECOMMENDATIONS GRADING AND EARTHWORK GENERAL: All grading should conform to the guidelines presented in the current edition of the California Building Code, the minimum requirements of the City of Carlsbad, and the recommended Grading Specifications and Special Provisions attached hereto, except where specifically superseded in the text of this report. PRE-GRADE MEETING: It is recommended that a pie-grade meeting including the grading contractor, the client, and a representative from Christian Wheeler Engineering be performed, to discuss the recommendations of this report and to address any issues that may affect grading operations. OBSERVATION OF GRADING: Continuous observation by the Geotechnical Consultant is 0 essential during the grading operation to confirm conditions anticipated by our investigation, to allow CWE 2120311.02R August 6, 2012 Page No. 7 0 adjustments in design criteria to reflect actual field conditions exposed, and to determine that the grading proceeds in general accordance with the recommendations contained herein. CLEARING AND GRUBBING: Site preparation should begin with the demolition of all existing improvements. The resulting debris as well as all vegetation and other deleterious materials in areas of the site to receive the proposed improvements and/or fill materials should be disposed of off-site. SITE PREPARATION: Existing fill, topsoil, and potentally compressible paralic deposits underlying proposed structures and settlement-sensitive improvements should be removed to the contact with competent native materials. Based on our subsurface explorations, the removal depth is expected to range from about 1 foot to possibly as much as 9 feet below existing grade. However, deeper removals may be necessary in areas of the site not investigated. We anticipate that the removal depths in the area of the proposed gymnasium will range from approximately 5 feet on the western portion of the building to approximately 8 feet on the eastern portion. We anticipate that the removal depths in the area of the proposed maintenance building will be approximately 3 to 4 feet. The horizontal limits of the removals should include all areas that will support settlement-sensitive improvements such as structures, parking lots, and hardsca?e, and should extend at least five feet outside the edges of such improvements or removal depth, whichever is less. In proposed parking and hardscape areas, the minimum lateral removal limits may be reduced to two feet. All areas cleaned out of unsuitable soils should be approved by the geotechnical engineer or his representative prior to replacing any of the excavated soils. The excavated materials, with thr exception of the expansive subsoil, can be replaced as properly compacted fill in accordance with the recommendations presented in the "Compaction and Method of Filling" section of our forthcoming geotechnical report. EXCAVATION CHARACTERISTICS: It is our opinion that anticipated cuts associated with likely grading operations may be achieved with conventional heavy duty grading equipment and light trenching equipment in good working order. PROCESSING OF FILL AREAS: Prior to placing any new fill soils in areas that have been cleaned out to receive fill and have been approved by the Geotechnical Consultant or his representative, the exposed soils should be scarified to a depth of 12 inches, moisture-conditioned, and compacted as described hereinafter. CWE 2120311.02R August 6, 2012 Page No. 8 S COMPACTION AND METHOD OF FILLING: In general, all structural fill placed at the site should be compacted to a relative compaction of at least 90 percent of its maximum laboratory dry density as determined by ASTM Laboratory Test Dl 557. Fills should be placed at or slightly above optimum moisture content, in lifts six to eight inches thick, with each lift compacted by mechanical means. Fills should consist of approved earth material, free of trash or debris, roots, vegetation, or other materials determined to be unsuitable by the Geotechnical Consultant. Fill material should be free of rocks or lumps of soil in excess of three inches in maximum dimension. Utility trench backfill within five feet of the proposed structure should be compacted to a minimum of 90 percent of its maximum dry density. TEMPORARY SLOPES: We anticipate that temporary excavation slopes up to about 12 feet high may be required for the construction of the proposed maintenance building. The excavations required for footing construction are considered as part of the temporary slopes. Cohesionless sands may be encountered in some of the temporary cut slope excavations. Therefore, temporary cuts should be excavated at an inclination of 1:1 or flatter. We recommend that our firm be contacted to have an engineering geologist observe the temporary cut slopes during grading to ascertain that no 5 unforeseen adverse conditions exist. If adverse conditions are identified, it may be necessary to flatten the slope inclination. No surcharge loads such as soil or equipment stockpiles, vehicles, etc. should be allowed within a distance from the top of temporary slopes equal to half the slope height. The contractor is solely responsible for designing and constructing stable, temporary excavations and may need to shore, slope, or bench the sides of trench excavations as required to maintain the stability of the excavation sides where the friable sands are exposed. The contractor's "competent person", as defined in the OSHA Construction Standards for Excavations, 29 CFR, Part 1926, should evaluate the soil exposed in the excavations as part of the contractor's safety process. In no case should slope height, slope inclination, or excavation depth, including utility trench excavation depth, exceed those specified in local, state, and federal safety regulations. Christian Wheeler Engineering should be immediately notified if zones of ptential instability, sloughing or raveling develop, and mitigation measures should be implementec prior to continuing work. SURFACE DRAINAGE: The drainage around the prcposed improvements should be designed to collect and direct surface water away from proposed Improvements toward appropriate drainage facilities. Rain gutters with downspouts that discharge runoff away from the structure into controlled drainage devices are recommended. CWE 2120311.02R August 6, 2012 Page No. 9 The ground around the proposed improvements should be graded so that surface water flows rapidly away from the improvements without ponding. In general, we recommend that the ground adjacent to structures be sloped away at a minimum gradient of two percent. Densely vegetated areas where runoff can be impaired should have a minimum gradient of five percent for the first five feet from the structure. It is essential that new and existing drainage patterns be coordinated to produce proper drainage. Drainage patterns provided at the time of construction should be maintained throughout the life of the proposed improvements. Site irrigation should be limited to the minimum necessary to sustain landscape growth. Over watering should be avoided. Should excessive irrigation, impaired drainage, or unusually high rainfall occur, zones of wet or saturated soil may develop. GRADING PLAN REVIEW: The final grading planshould be submitted to this office for review in order to ascertain that no additional recommendations are needed due to changes in the anticipated construction. Our firm should be notified of changes to the proposed project that could necessitate revisions of or additions to the information contained herein. 0 FOUNDATIONS GENERAL: Based on our findings and engineering judgment, the proposed improvements may be supported by conventional shallow continuous and isolated spread footings. This assumes that the site preparation recommendations will be adhered to. The following recommendations are considered the minimum based on soil conditions and are not intended to be lieu of structural considerations. All foundations should be designed by a qualified engineer. FOUNDATION DIMENSIONS: Spread footings supporting the proposed athletic and maintenance structures should be embedded at least 18 inches below finish pad grade. Continuous footings should have a minimum width of 12 inches. Isolated footings and retaining wall footings should have a minimum width of 24 inches. Continuous, footings supporting minor structures such as the proposed bleachers, press box, and dugouts, and miscellaneous exterior improvements should be embedded at least 12 inches below finish pad grade, and should be at least 12 inches wide. BEARING CAPACITY: Spread footings supporting the proposed athletic and maintenance structures with the minimum dimensions previously described may be designed for an allowable soil bearing is pressure of 2,500 pounds per square foot (psf). This value may be increased by 600 psf for each 0 CWE 2120311.02R August 6, 2012 Page No. 10 additional foot of embedment depth and 400 psf for each additional foot of width, up to a maximum of 4,000 psf. Spread footings for any proposed minor structures and exterior miscellaneous improvements may be designed for an allowable soil bearing pressure of 2,000 pounds per square foot (ps. This value may be increased by 600 psf for each additional foot of embedment depth and 400 psf for each additional foot of width, up to a maximum of 4,000 psf. The bearing values may also be increased by one-third for combinations of temporary loads such as those due to wind or seismic loads. FOOTING REINFORCING: Reinforcement requirem.snts for foundations should be provided by a structural engineer. However, based on the expected soil conditions, we recommend that the minimum reinforcing for continuous footings consist of at least two No. 5 bars positioned near the bottom of the footing and two No. 5 bars positioned near the top of the footing. However, we recommend that the minimum reinforcing for continuous footings supporting miscellaneous improvements consist of at least one No. 5 bar positioned near the bottom of the footing and one No. 5 bar positioned near the top of the footing. LATERAL LOAD RESISTANCE: Lateral loads agains: foundations may be resisted by friction between the bottom of the footing and the supporting soil, and by the passive pressure against the footing. The coefficient of friction between concrete and soil may be considered to be 0.35. The passive resistance may be considered to be equal to an equivalent fluid weight of 350 pounds per cubic foot. These values are based on the assumption that the fcotings are poured tight against undisturbed soil. If a combination of the passive pressure and friction is used, the friction value should be reduced by one-third. SEISMIC DESIGN FACTORS: The seismic design factors applicable to the subject site are provided below. The seismic design factors were determined in accordance with the 2010 California Building Code, based on the 2009 International Building Code. The site coefficients and adjusted maximum considered earthquake spectral response acceleration parameters are presented in the table provided on the following page: TABLE I: SEISMIC DESIGN FACTORS Site Coordinates: Latitude Longitude 33.1624° -117.35350 Site Class D Site Coefficient Fa 1.0 Site Coefficient F- 1.5 Spectral Response Acceleration at Short Periods S 1.338 g CWE 2120311.02R August 6, 2012 Page No. 11 Spectral Response Acceleration at 1 Second Period Si 0.504 g Sais=FaSs 1.338 g Sart=FvSi 0.756 g SDS=2/3*SrvfS 0.892 g SDI_2/3*SM1 0.50 g Probable ground shaking levels at the site could range from slight to moderate, depending on such factors as the magnitude of the seismic event and the distance to the epicenter. It is likely that the site will experience the effects of at least one moderate to large earthquake during the life of the proposed improvements. EXPANSIVE CHARACTERISTICS: The recommended site preparation procedures are expected to result in the anticipated foundation soils having a very low expansion potential (EI<20). The recommendations presented in this report reflect this condition. SETTLEMENT CHARACTERISTICS: The anticipated total and differential settlement is expected to be less than about one inch and one inch over forty feet, respectively, provided the recommendations presented in this report are followed. It should be recognized that minor cracks . normally occur in concrete slabs and foundations due to concrete shrinkage during curing or redistribution of stresses, therefore some cracks should be anticipated. Such cracks are not necessarily an indication of excessive vertical movements. FOUNDATION EXCAVATION OBSERVATION: All footing excavations should be observed by Christian Wheeler Engineering prior to placing of forms and reinforcing steel to determine whether the foundation recommendations presented herein are followed and that the foundation soils are as anticipated in the preparation of this report. All footing excavations should be excavated neat, level, and square. All loose or unsuitable material should be removed prior to the placement of concrete. FOUNDATION PLAN REVIEW: The final foundation plan and accompanying details and notes should be submitted to this office for review. The intent of our review will be to verify that the plans used for construction reflect the minimum dimensioning and reinforcing criteria presented in this section and that no additional criteria are required due to changes in the foundation type or layout. It is not our intent to review structural plans, notes, details, or calculations to verify that the design engineer has correctly applied the geotechmcal design values. It is the responsibility of the design engineer to properly design/specify the foundations and other structural elements based on the requirements of the structure and considering the information presented in this report. CWE 2120311.02R August 6, 2012 Page No. 12 'SOLUBLE SULFATES: The water soluble sulfate content of a selected soil sample from the site was determined in accordance with California Test Method 417. The results of this test indicate that the soil sample had a soluble sulfate content of 0.003 percent. Soils with a soluble sulfate content of less than 0.1 percent are considered to be negligible. Therefore, no special requirements are considered necessary for the concrete mix design. ON-GRADE SLABS GENERAL: It is our understanding that the floor system for the proposed athletic complex building and the proposed maintenance building will consist of on-grade concrete floor slabs. The following recommendations are considered the minimum slab requirements based on the anticipated soil conditions and are not intended to be in lieu of structural considerations. The slabs should be designed by the project engineer. INTERIOR FLOOR SLABS: The minimum floor slab thickness for the proposed athletic complex and maintenance structures should be five inches (actual) and the floor slab should be reinforced with at least No. 3 reinforcing bars placed at 18 inches on center each way. The minimum floor slab thickness for the proposed miscellaneous structures should be four inches (actual) and the floor slab should be reinforced with at least No. 3 reinforcing bars placed at 18 inches on center each way. Slab reinforcement should be supported on chairs such that the reinforcing bars are positioned at mid-height in the floor slab. The slab reinforcement should extend into the perimeter foundations at least six inches. UNDER-SLAB VAPOR RETARDERS: Steps should be taken to minimize the transmission of moisture vapor from the subsoil through the interior slabs where it can potentially damage the interior floor coverings. Local industry standards typically include the placement of a vapor retarder, such as plastic, in a layer of coarse sand placed directly beneath the concrete slab. Two inches of sand are typically used above and below the plastic (four inches total). This is the most common under-slab vapor retarder system used in San Diego County. The vapor retarder should be at least 15-mil plastic with sealed seams and should extend at least 12 inches down the sides of the interior and perimeter footings. The sand should have a sand equivalent of at least 30, and contain less than 10% passing the Number 100 sieve and less than 5% passing the Number 200 sieve. It should be understood that slab concrete contains free water and should be allowed to reach equilibrium in an environment similar to that anticipated in the completed structure prior to installing CWE 2120311.02R August 6, 2012 Page No. 13 floor coverings. We recommend that the flooring installer perform standard moisture vapor emission tests prior to the installation of all moisture-sensitive floor coverings in accordance with ASTM F1869 "Standard Test Method for Measuring Moisture Vapor Emission Rate of Concrete Subfloor Using Anhydrous Calcium Chloride". EXTERIOR CONCRETE FLATWORK: Exterior concrete slabs on grade should have a minimum thickness of four inches and should be reinforced with at least No. 3 bars placed at 18 inches on center each way (ocew). Where patio slabs, walkways and porch slabs abut perimeter foundations, they should be doweled into the footings. Driveway slabs should have a minimum thickness of five inches and should be reinforced with at least No. 4 bars placed at 18 inches on center each way (ocev). Driveway slabs should be provided with a thickened edge at least 18 inches deep and 6 inches wide. All slabs should be provided with weakened plane joints in accordance with the American Concrete Institute (ACT) guidelines. A concrete mix with a 1-inch maximum aggregate size and a water/cement ratio of less than 0.6 is recommended for exterior slabs. Lower water content wil decrease the potential for shrinkage cracks. Consideration should be given to using a concre:e mix for the driveway that has a minimum compressive strength of 3,000 pounds per square inch. This suggestion is meant to address early driveway use prior to full concrete curing. Both coarse and fine aggregate should conform to the latest edition of the "Standard Specifications for Public Works Construction" ('Greenbook"). Special attention should be paid to the method of concrete curing to reduce the potential for excessive shrinkage and resultant random cracking. It should be recognized that minor cracks occur normally in concrete slabs due to shrinkage. Some shrinkage cracks should be expected and are not necessarily an indication of excessive movement or structural distress. EARTH RETAINING WALLS FOUNDATIONS: Foundations for any proposed retaining walls should be designed in accordance with the recommendations for shallow foundations presented previously in this report. PASSIVE PRESSURE: The passive pressure for the anticipated foundation soils may be considered to be 350 pounds per square foot per foot of depth. The upper foot of embedment should be neglected CWE 2120311.02R August 6, 2012 Page No. 14 when calculating passive pressures, unless the foundation aDuts a hard surface such as a concrete slab. The passive pressure may be increased by one-third for seismic loading. The coefficient of friction for concrete to soil may be assumed to be 0.35 for the resistance to lateral movement When combining frictional and passive resistance, the friction should be reduced by one-third. ACTIVE PRESSURE: The active soil pressure for the design of "unrestrained" and "restrained" earth retaining structures with level backfill may be assumed to be equivalent to the pressure of a fluid weighing 35 and 55 pounds per cubic foot (pcf), respectively. An additional; 15 pcf may be assumed for 2:1 (horizontal to vertical) sloping conditions. These pressures do not consider any other surcharge. If any are anticipated, this office should be contacted for the :aecessary increase in soil pressure. These values are based on a drained backfill condition. Seismic lateral earth pressures may be assumed to equal an inverted triangle starting at the bottom of the wall with the maximum pressure equal to 7H pounds per square foot (where H = wall height in feet) occurring at the top of the wall. WATERPROOFING AND WALL DRAINAGE SYSTEMS: The need for waterproofing should be evaluated and designed by others. If required, the project architect should provide (or coordinate) waterproofing details for the retaining walls. The design values presented above are based on a drained backfill condition and do not consider hydrostatic pressures. Unless hydrostatic pressures are incorporated into the design, the retaining wall designer should provide a detail for a wall drainage system. Typical retaining wall drain system details are presanted as Plate No. 13 of this report for informational purposes. Additionally, outlets points for the retaining wall drain system should be coordinated with the project civil engineer. BACKFILL: All backfill soils should be compacted to at least 90 percent relative compaction. Expansive or clayey soils should not be used for backfill material. The wall should not be backfllled until the masonry has reached an adequate strength. PRELIMINARY PAVEMENT SECTIONS TRAFFIC INDEX: It is our assumed that the proposed paved areas will include parking areas and access driveways to the site for all vehicles including trash trucks. In consideration of this traffic conditions we have assumed a Traffic Index of 4.5 for the proposed parking areas and 5.0 for the main CWE 2120311.02R August 6, 2012 Page No. 15 access driveways. The project.client and/or civil engineer should determine if these assumptions are appropriate, and if revised Traffic Indexes are warranted. R-VALUE TEST: Based on our findings, it is our opinion that the on-Site soils have relatively good pavement support characteristics (estimated R-Value30). The following pavement sections should be considered preliminary and should be used for planning purposes only. Final pavement designs should be determined after R-value tests have been performed in the actual subgrade material. PRELIMINARY STRUCTURAL SECTION: It is our understanding that the paving materials have not yet being determined, and may consist of asphalt concrete, Portland cement concrete (PCC), and/or pervious payers. Based on the above parameters, the following minimum preliminary pavement sections are recommended. TABLE II: PRELIMINARY ASPHALT CONCRETE PAVEMENT SECTION Proposed Use R-Value Traffic Index Asphalt Concrete Base Parking Lots 30 4.5, 4.0 inches* 4.0 inches Main Driveways 30 5.0 4.0 inches* 4.0 inches City of Carlsbad Standard TABLE III: PRELIMINARY PCC PAVEMENT SECTIONS Proposed Use R-Value Portland Cement Concrete* Base Parking Lots 30 6.0 inches N/A Main Driveways 30 7.0 inches N/A * Reinforcement per structural engineer recommendations. Concrete sections for stamped concrete should be measured below the stamped depth. TABLE IV: PRELIMINARY PAVER PAVEMENT SECTION Proposed Use R-Value Paver/Sand Base Parking Lots 30 3.0 inches*/1.0 inch 4.5 inches Main Driveways 30 3.0 inches*/1.0 inch 5.5 inches *Assumed Concrete pads should be constructed in front of the trash dumpster storage areas where the trash trucks will stop and pick up the dumpsters. The concrete pads should be at least seven inches thick. If the CWE 2120311.02R August 6, 2012 Page No. 16 0 subgrade soil consists of imported soil, the concrete pads may be placed directly on the subgrade soil (no base necessary). Minimum reinforcement should consist of No. 4 bars placed at 12 inches on center each way. Prior to placing the base material, the subgrade soils should be scarified to a depth of 12 inches, moisture conditioned and compacted to at least 95 percent of its maximum dry density. The base material could consist of Crushed Aggregate Base (CAB) or Class II Aggregate Base. The Crushed Aggregate Base should conform to the requirements set forth in Section 200-2.2 of the Standard Specifications for Public Works Construction. The Class II Aggregate Base should conform to requirements set forth in Section 26-1.02A of the Standard Specifications for California Department of Transportation. As an alternate, the base material for the pavements may consist of Crushed Miscellaneous Base (recycled base material) which conforms to the requirements set forth in Section 200-2.4 of the Standard Specifications for Public Works Construction. It should be noted, however, that Crushed Miscellaneous Base material has lower durability characteristics than Crushed Aggregate Base or Class II Aggregate Base, which may result in a shorter pavement life. As such, the owner of the project should approve the use of this material for the pavement base. Concrete pavements construction should comply with the requirements set fourth in Sections 201-.1.2 and 302-6 of the Standard Specifications for Public Works Construction (concrete Class 520-A-2500). All paving methods and materials should conform with good engineering and paving practices and to the requirements of the City of Carlsbad. LIMITATIONS REVIEW, OBSERVATION AND TESTING The recommendations presented in this report are contingent upon our review of final plans and specifications. Such plans and specifications should be made available to the geotechnical engineer and engineering geologist so that they may review and verify their compliance with this report and with the California Building Code. It is recommended that Christian Wheeler Engineering be retained to provide continuous soil engineering services during the earthwork operations. This is to verify compliance with the design concepts, specifications or recommendations and to allow design changes in the event that subsurface conditions differ from those anticipated prior to start of construction. CWE 2120311.02R August 6, 2012 Page No. 17 UNIFORMITY OF CONDITIONS The recommendations and opinions expressed in this report reflect our best estimate of the project requirements based on an evaluation of the subsurface soil conditions encountered at the subsurface exploration locations and on the assumption that the soil conditions do not deviate appreciably from those encountered. It should be recognized that the performance of the foundations and/or cut and fill slopes may be influenced by undisclosed or unforeseei variations in the soil conditions that may occur in the intermediate and unexplored areas. Any unusual conditions not covered in this report that may be encountered during site development should be brought to the attention of the geotechnical engineer so that he may make modifications if necessary. CHANGE IN SCOPE This office should be advised Of any changes in the project scope or proposed site grading so that we may determine if the recommendations contained herein are appropriate. This should be verified in writing or modified by a written addendum. TIME LIMITATIONS The findings of this report are valid as of this date. Changes in the condition of a property can, however, occur with the passage of time, whether they be due to natural processes or the work of man on this or adjacent properties. In addition, changes in the Standards-of-Practice and/or Government Codes may occur. Due to such changes, the findings of this report may be invalidated wholly or in part by changes beyond our control. Therefore, this report should not be relied upon after a period of two years without a review by us verifying the suitability of the conclusions and recommendations. PROFESSIONAL STANDARD In the performance of our professional services, we comply with that level of care and skill ordinarily exercised by members of our profession currently practicing under similar conditions and in the same locality. The client recognizes that subsurface conditions may vary from those encountered at the locations where our borings, surveys, and explorations are made, and that our data, interpretations, and recommendations be based solely on the information obtained by us. We will be responsible for those data, interpretations, and recommendations, but shall not be responsible for the interpretations CWE 2120311.02R August 6, 2012 Page No. 18 by others of the information developed. Our services consist of professional consultation and observation only, and no warranty of any kind whatsoever, express or implied, is made or intended in connection with the work performed or to be performed by us, or by our proposal for consulting or other services, or by our furnishing of oral or written reports or findings. CLIENT'S RESPONSIBILITY It is the responsibility of the Clients, or their representatives, to ensure that the information and recommendations contained herein are brought to the attention of the structural engineer and architect for the project and incorporated into the project's plans and specifications. It is further their responsibility to take the necessary measures to insure that the contractor and his subcontractors carry out such recommendations during construction. FIELD EXPLORATIONS Eight subsurface explorations were made on July 5, 2012 at the locations indicated on the Site Plan and Geotechnical Map included herewith as Plate No. 1. These explorations consisted of borings drilled utilizing a truck-mounted drill rig and logging an existing slope. The fieldwork was conducted under the observation and direction of our engineering geology personnel. The explorations were carefully logged when made. The boring logs and slope log are presented on Plate Numbers 2 through 10. The soils are described in accordance with the Unified Soils Classification. In addition, a verbal textural description, the wet color, the apparent moisture, and the density or consistency is provided. The density of granular soils is given as very loose, loose, medium dense, dense or very dense. The consistency of silts or clays is given as either very soft, soft, medium stiff, stiff, very stiff, or hard. Relatively undisturbed drive samples were collected using a modified California sampler. The sampler, with an external diameter of 3.0 inches, is 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 falling 30 inches in general accordance with ASTM D 3550-84. The driving weight is permitted to fall freely. The number of blows per foot of driving, or as indicated, is presented on the boring logs as an index to the relative resistance of the sampled materials. The samples were removed from the sample barrel in the brass rings, and sealed. Bulk samples of the CWE 2120311.02R August 6, 201:2 Page No. 19 encountered earth materials were also collected. Samples were transported to our laboratory for testing. LABORATORY TESTING Laboratory tests were performed in accordance with the generally accepted American Society for Testing and Materials (ASTM) test methods or suggested procedures. A brief description of the tests performed is presented below: CLASSIFICATION: Field classifications were verified in the laboratory by visual examination. The final soil classifications are in accordance with the Unified Soil Classifica- tion System. MOISTURE-DENSITY: In-place moisture contents and dry densities were determined for selected soil samples in accordance with ATM D 2937. The results are summarized in the boring logs. .c) MAXIMUM DRY DENSITY AND OPTIMUM MOISTURE CONTENT: The - maximum dry density and optimum moisture content of selected soil samples were determined in the laboratory in accordance with ASTM D 1557, Method A. The results of this test are presented on Plate Number 11. DIRECT SHEAR TEST: A direct shear test was performed on selected samples of the on- site soils in accordance with ASTM D 3080. The results of these tests are presented on Plate Number 11. GRAIN SIZE DISTRIBUTION: The grain size distribution of selected soil samples was determined in accordance with ASTM D 422. The results of these tests are presented on Plate Number 11. COLLAPSE POTENTIAL TEST: Collapse potential tests were performed on selected undisturbed soil samples. The tests were generally performed in accordance with ASTM D 5333.The test results are presented on Plate Number 12. 0 CWE 2120311.02R August 6, 2012 Page No. 20 SOLUBLE SULFATES: The soluble sulfate content of a selected soil sample was determined in accordance with California Test Method 417. The test results are presented on Plate Number 12. R-VALUE TEST: An R- Value test was performed on a selected soil sample. The test was generally performed in accordance with California Test Method 301. The results of the test are presented on Plate Number 12. I REVISIONS: A REVISET i-lOUSE - pp GE Mark T. Mouse John Dodge org H.o0_ Street Sod. gee Uj DO 04 SaoDSgo,CA SortS Sw*ivaw*Sdgtwtn HSU.. S Dodge Dodgr. ire >- <ac) oc < 3cc zo -. 0 .-.- 2(0 ctoJ PRELIMINARY NOT FOR CONSTRUCTION SCALE: I"o30-O DATE: 06-04-12 ATHLETIC FACILITY SITE PLAN SCHEMATIC PLAN A1.1 / - - - - - — - 4 sf BE- -: - --.- - - - OP6.7' 000 NG LOT / EL. +41.0' ./- woo r lop - Q0p 03 QLUL —------ Th I - Qop7 L- - I -----— -----*\ POTT 'i o-7 E&CHERYL I -- jAeiG DUFFIELD I of CO MPLEX ATHLETIC LD BUILDING — to - E.+40.O I (Wi&TORAGE [_7 /U.. HIL LOW -- ( 15! I7 * I fQo6L7 rI "i// m :1PARKING B-2 Q ---- LU LU 777 co DUG OUT BUILDING HE EF PRESS EL - - - 7;4107LINE . - - --- - - - / - - --.- --- -- - CARLSBAnPI, CWE LEGEND B-8 APPROXIMATE BORING LOCATION 4 SL-1 APPROXIMATE SLOPE LOG LOCATION I' IJ APPROXIMATE GEOLOGIC CONTACT Qaf ARTIFICIAL FILL UNDERLAIN BY Q OLD PARALIC DEPOSITS Q0p6.7 OLD PARALIC DEPOSITS *NOTE: TOPSOILS NOT MAPPED V Li -;- - — --------- 1. - . -------------- 0 75' 150' SCALE: 1" = 75' PROPOSED ATHLETIC FIELD IMPROVEMENTS ARMY AND NAVY ACADEMY CARLSBAD, CALIFORNIA SITE PLAN AND GEOTECHNICAL MAP DATE: August 2012 JOB NO.: 2120311.02R CHRISTIAN WHEELER BY: DBA/TSW/JDB PLATE NO.: 1 ENGINEERING S LOG OF TEST BORING B—i Sample Type and Laboratory Test Legend Cal Modified California Sampler CK Chunk Sample SPT Standard Penetration Test DR Density Ring Date Drilled: 7/5/2012 Equipment: Unimog Marl M5 ST Shelby Tube Logged by: TSW Auger Type: Hollow Stem MD Maximum Density DS Direct Shear SO4 Soluble Sulfates Con Consolidation Existing Elevation: 39 feet Drive Type: 140 lb/so in SA Sieve Analysis El Expansion Index HA Hydrometer R-Val Resistance Value Proposed Elevation: 39.5 feet Depth to Water: N/A SE Sand Equivalent Chl Soluble Chlorides P1 Plasticii Index Res 3H&Resistivav SUMMARY OF SUBSURFACE CONDITIONS z z 0 C' Unified Soil Classification System) (based on F..2 Id Id 'it u z ' a CI OO Of-s Id Id Q Id 0 39 SM Artificial Fill (Oaf): Brown to dark brown, damp to moist, loose, fine- - - - - - - MD - - to medium-grained, SILTY SAND,with minor debris. DS - 7 Cal - S -34 SM Old Paralic Deposits (Oop6-7: Reddish-brown, moist, loose to medium - 21 - Cal - dense, fine- to coarse-grained, SILTY SAND. CL — El 10-- 29 25 Cal - 28.1 94.6 sp-srsi Reddish-brown and gray, moist, medium dense, POORLY GRADED SAND with silt. Friable. 15— - 24 - 37 Cal 4.6 108.3 Becomes moist to very moist at 20 feet. 47 Cal 14 1l( 20—-19 — - - Boring terminated at 20 feet. 25— - 14 30-- 9 Symbol Legend PROPOSED ATHLETIC FIELD IMPROVEMENTS Groundwater Army and Navy Academy, Carlsbad, California Apparent Seepage CHRiSTIAN WHEELER BY: MAH DATE: August 2012 * No Sample Recovery E N C I N E E K I N C ** Erroneous Blow Count JOB NO.: 2120311.02R PLATE NO.: 2 (rocks present) S S LOG OF TEST BORING B-2 Sample Type and Laboratory Test Legend Cal Modified California Sampler CK Chunk Sample SPT Standard Penetration Test DR Density Ring Date Drilled: 7/5/2012 Equipment: Unimog Marl M5 ST Shelby Tube Logged by: TSW Auger Type: Hollow Stem MD Maximum Density DS Direct Shear SO4 Soluble Sulfates Con Consolidation Existing Elevation: 40.5 feet Drive Type: 140 lb/30 in SA Sieve Analysis El Expansion Index I -IA Hydrometer R-Val Resistance Value Proposed Elevation: 39.5 feet Depth to Water: N/A SE Sand Equivalent ChI Soluble Chlorides P1 Plasticii r Index Res 3H& Resistivity Q - z 0 o SUMMARY OF SUBSURFACE CONDITIONS 1- z z Unified Soil Classification Systena) (based on on H.2 ... I- I - — z -z lei' M tia 0 405 SM Topsoil: Brown to dark brown, damp to moist, loose to medium dense, — — — — — — — - - fine- to medium-ned. SILTY SAND. - - - — — - - SM Old Paralic Deposits (Oop6-7): Reddish-brown, moist, loose to medium 20 Cal 6.2 115.8 - dense, fine- to coarse-grained, SILTY SAND. 5 - .35.5 SM Reddish-brown, moist, medium dense, fine- to coarse-gained, 33 Cal - CP - - ----- SILTY SAND with clay. 10-- 30.5 - - 42 Cal 11.2 117.2 - Becomes light reddish-brown. Sp-SP-SM Light reddish-brown, moist, dense, medium- to coarse-grained, - - - - - - - 25.5 S~I 15 POORLY GRADED SAND with silt. Friable; - - Boring terminated at 16 feet. - -- 20- 20.5 25- - 15.5 30- - 10.5 Symbol Legend PROPOSED ATHLETIC FIELD IMPROVEMENTS Y Groundwater Army and Navy Academy, Carlsbad, California Apparent Seepage CHRISTIAN WHEELER- BY: MAH DATE: August 2012 No Sample Recovery I- N C I N E E R. I N C Erroneous Blow Count JOB NO.: 2120311.02R PLATE NO.: 3 (rocks present) S S LOG OF TEST BORING B-3 Sample Type and Laboratory Test Legend Cal Modified California Sampler CK Chunk Sample Penetration Test DR Density Ring SPTStandard Date Drilled: 7/5/2012 Equipment: Uninsog Marl M5 ST Shelby Tube Logged by: TSW Auger Type: Hollow Stem MD Maximum Density DS Direct Shear SO4 Soluble Sulfates Con Consolidation Existing Elevation: 39 feet Drive Type: 140 1/30 in SA Sieve Analysis El Expansion Index I-iA Hydrometer R-Val Resistance Value Proposed Elevation: 40.5 feet Depth to Water: N/A. SE Sand Equivalent CM Soluble Chlorides PS Plasticii r Index Res 3H&Resistivav z 0 0 z di I.) oQq i-s SUMMARY OF SUBSURFACE CONDITIONS j z z C' 0 o Unified Soil Classification System) (based on we iz 14 Cl, L) Z ' C 0f.s fia Cl) 'iS 0 S Topsoil: Brown to dark brown, moist, loose to medium dense, — — — — — — — - - fine- to medium-grned. SILTY SAND. - - - - - SM Old Paralic Deposits (Oop6-7: Reddish-brown, moist, loose to medium 10 Cal - - dense, fine- to coarse-grained, SILTY SAND. SM Reddish-brown, moist, medium dense to dense, fine- to coarse-grained, SA 5- .34 SILTY SAND with clay. 43 Cal 10.5 127.5 El - SO4 10-- 29 - - 59 Cal CP Lightreddish-brown. Sp- SM Light reddish-brown and dark gray, moist, dense, medium- to coarse- - - - 15 — - 24 grained, POORLY GRADED SAND with silt. Friable. 1~1 -7.7— —77_ — — - - Boring terminated at 16 feet. 20— - 19 25— 14 30 - - 9 Symbol Legend PROPOSED ATHLETIC FIELD IMPROVEMENTS Y Groundwater Army and Navy Academy, Carlsbad, California Apparent Seepage CHRISTIAN WHEELER BY: MAH I DATE: August 2012 * No Sample Recovery E N C l N E E P. I N C Erroneous Blow Count JOB NO.: 2120311.0211 PLATE NO.: 4 (rocks peesen LOG OF TEST BORING B-4 Sample Type and Laboratory Test Legend Cal Modified California Sampler CK Chunk Sample Standard Penetration Test DR Density Ring SPT Date Drilled: 7/5/2012 Equipment: Unirnog Marl MS ST Shelby Tube Logged by: TSW Auger Type: Hollow Stem MD Maximum Density DS Direct Shear SO4 Soluble Sulfates Con Consolidation Existing Elevation: 47 feet Drive Type: 140 1D/30 in SA Sieve Analysis El Expansion Index HA Hydrometer R-Val Resistance Value Proposed Elevation: 46 feet Depth to Water: N/A SE Sand Equivalent ChI Soluble Chlorides P1 Plasticit i Index Res 3H&Resistivbv z 0 z o ,-1 n SUMMARY OF SUBSURFACE CONDITIONS Unified Soil Classification System) 1-' 0 l- (based on H- H H cit Z -z 00 iu - 0 H H cit n ci, 0 47 SM Topsoil: Brown to dark brown, moist, loose to medium dense, — — — — — — — - - fine- to medium-grained, SILTY SAND. SM Old Paralic Deposits (Oop6-7): Reddish-brown, moist, loose to medium - - dense, fine- to coarse-grained, SILTY SAND. 5- -42 19 Cal 9.7 122.3 SP-SM Light to medium reddish-brown, moist, medium dense, medium- to coarse - - 10 -- 37 grained, POORLY GRADED SAND with silt. Friable. - - 34 Cal 6.8 111.1 15-- 32 - Light reddish-brown to dark gray at 15 feet. — 29 Cal - - Boring terminated at 16 feet. 20— - 17 25—-12 30- -7 Symbol Legend PROPOSED ATHLETIC FIELD IMPROVEMENTS Groundwater Army and Navy Academy, Carlsbad, California Apparent Seepage CHRISTIAN WHEELER. BY: MAH DATE: August 2012 * No Sample Recovery E N C I N E E P. I N C ** Erroneous Blow Count JOB NO.: 2120311.0211 PLATE NO.: 5 (rocks present) S S LOG OF TEST BORING B-5 Sample Type and Laboratory Test Legend Cal Modified California Sampler CK Chunk Sample SPT Standard Penetration Test DR Density Ring Date Drilled: 7/5/2012 Equipment: Unimog Marl M5 ST Shelby Tube Logged by: TSW Auger Type: Hollow Stem MD Maximum Density DS Direct Shear SO4 Soluble Sulfates Con Consolidation Existing Elevation: 39.5 feet Drive Type: 140 Lb/30 in SA Sieve Analysis El Expansion Index HA Hydrometer R-Val Resistance Value Proposed Elevation: 39 feet Depth to Water: N/A SE Sand Equivalent Clii Soluble Chlorides P1 Ptasticii i Index Res 3H&Resistivax B z ° 0 SUMMARY OF SUBSURFACE CONDITIONS Z (based on on In HFn Bz Unified Soil Classification System) En H to z PP pt- 0k-a H H 0 i'S H U B ,, 0 39.5 SM Old Paralic Deposits (Oop6-7): Reddish-brown, moist, loose to medium - - - — - — — - - . dense, fine- to coarse-grained, SILTY SAND. - - Medium dense to dense. 52 Cal 5.0 102.3 SP-SM Reddish brown and gray, moist, medium dense to dense, medium- to 5—-34.5 coarse -grained, POORLY GRADED SAND, with silt. Friable. 39 Cal 3.8 100.2 10— - 29.5 - - Boring terminated at 16 feet. 15-- 24.5 20— - 19.5 25— - 14.5 30 -- 9.5 Symbol Legend PROPOSED ATHLETIC FIELD IMPROVEMENTS Y Groundwater Army and Navy Academy, Carlsbad, California Apparent Seepage CHRiSTIAN WHEELER - BY: MAH No DATE: August 2012 * No Sample Recovery E N C I N E E 5. I N C ** Erroneous Blow Count JOB NO.: 2120311.02R PLATE NO.: 6 (rocks present) C S LOG OF TEST BORING B-6 Sample Type and Laboratory Test Legend Cal Modified California Sampler CK Chunk Sample Standard Penetration Test DR Density Ring SPT Date Drilled: 7/5/2012 Equipment: Unimog Marl M5 ST Shelby Tube Logged by: TSW Auger Type: Hollow Stem MD Maximum Density DS Direct Shear SO4 Soluble Sulfates Con Consolidation Existing Elevation: 49.5 feet Drive Type: 140 lb/30 in SA Sieve Analysis El Expansion Index HA Hydrometer R-Val Resistance Value Proposed Elevation: 39.5 feet Depth to Water: N/A SE Sand Equivalent Chi Soluble Chlorides P1 Plasticit r Index Res 3H & Resistivity H z 2 SUMMARY OF SUBSURFACE CONDITIONS rn Unified Soil Classification System) (based on I-. 0 495 SM Old Paralic Deposits (Oop6-7): Reddish-brown, damp to moist, loose SA - - . to medium dense fine- o cogramned, SILTY SANJ. MD - - Moist. 46 Cal DS - Medium dense. 5 - 44.5 - Dense. 55 Cal - 4.0 114.9 iS SP-SM Light reddish brown and gray, moist, dense, medium- to coarse- 10- • grained, POORLY GRADED SAND, with silt. Friable. - - 50 Cal CP iD ,45 62 Cal - 3.2 107.5 - - - Boring terminated at 16 feet. 20- 29.5 25— - 24.5 30 19.5 Symbol Legend PROPOSED ATHLETIC FIELD IMPROVEMENTS Y Groundwater W Army and Navy Academy, Carlsbad, California Apparent Seepage CHIUSTIAN WHEELER- BY: MAH DATE: August 2012 No Sample Recovery ENGINE E P. IN G ** Erroneous Blow Count JOB NO.: 2120311.02R PLATE NO.: 7 (rocks present) S S Ll LOG OF TEST BORING B-7 Sample Type and Laboratory Test Legend Cal Modified California Sampler CK Chunk Sample Standard Penetration Test DR Density Ring SPT Date Drilled: 7/5/2012 Equipment: Unimog Marl M5 ST Shelby Tube Logged by: TSW Auger Type: Holiow Stem MD Maximum Density DS Direct Shear SO4 Soluble Sulfates Con Consolidation Existing Elevation: 41.0 feet Drive Type: 140 1b/30 in SA Sieve Analysis El Expansion Index I -IA Hydrometer R-Val Resistance Value Proposed Elevation: 45.5 feet Depth to Water: N/P. SE Sand Equivalent Clii Soluble Chlorides N Plasticit i Index Res 3H&Resktivitv z 0 I-I o n z 0 o -U SUMMARY OF SUBSURFACE CONDITIONS H H'' CA Unified Soil Classification System) (based on I ° H H U) Z - Z H a iii 0 'U SM Old Paralic Deposits (Oop6-7): Light reddish-brown, damp to moist, — — — — — — - - loose to medium dense, fine- to medium-grained, SILTY SAND. - - 25 Cal Moist and medium dense. 5—-36 49 Cal - - Boring terminated at 6 feet. — to -3! 15-- 26 20-- 21 25— - 16 30-- ii Symbol Legend PROPOSED ATHLETIC FIELD IMPROVEMENTS Groundwater W Army and Navy Academy, Carlsbad, California Apparent Seepage CH1USTAN WHEELER- BY: MAH No Sample Recovery DATE: August 2012 E N C I N E fi P. I N C ** Erroneous Blow Count OB NO.: 2120311.02R F PLATE NO.: 8 (rocks present) LOG OF TEST BORING B-8 Sample Type and Laboratory Test Legend Cal Modified California Sampler CK Chunk Sample Standard Penetration Teat DR Density Ring SET Date Drilled: 7/5/2012 Equipment: Unimog Marl MS ST Shelby Tube Logged by: TSW Auger Type: Hollw Stem MD Maximum Density DS Direct Shear SO4 Soluble Sulfates Con Consolidation Existing Elevation: 40.0 feet Drive Type: 140 lb/30 in SA Sieve Analysis El Expansion Index I -IA Hydrometer R-Val Resistance Value Proposed Elevation: 39.5 feet Depth to Water: N/A SE Sand Equivalent Ch1 Soluble Chlorides P1 PlmtjciraIndex Res H&Resistivitv z 0 0 ill z SUMMARY OF SUBSURFACE CONDITIONS 0 0 . I., Unified Soil Classification Systen) Cn (based on Z e.lZ a ., 5') n In 0 40 SM Topsoil): Brown, moist, loose to medium dense, - - - - - - R-Val - - fine- to medium-grained, SILTY SAND. 20 L - SM Old Paralic Deposits (Oop6-7): Reddish-brown, mois:, loose to - - medium dense, fine- to medium-grained, SILTY SAND 5- - -35 - _rr_ 21 LaL - - Boring terminated at 6 feet. -- 10-- 30 15-- 25 20— - 20 25— - 15 30- -10 Symbol Legend PROPOSED ATHLETIC FIELD IMPROVEMENTS Groundwater Army and Navy Academy, Carlsbad, California Apparent Seepage CHPJSTIAN WHEELEK BY: MAH DATE: August 2012 * No Sample Recovery E N C I N E E P. I N C ** Erroneous Blow Count JOB NO.: 2120311.02R PLATE NO.: 9 (rocks present) SLOPE LOG SL-1 Sample Type and Laboratory Test Legend Cal Modified California Sampler CK Chunk Sample Standard Penetration Test DR Density Ring SPT Date Drilled: 7/5/2012 Equipment: Unitnog Marl M5 ST Shelby Tube Logged by: TSW Auger Type: Hollbw Stem MD Maximum Density DS Direct Shear SO4 Soluble Sulfates Con Consolidation Existing Elevation: 45.0 feet Drive Type: 140 ib/30 in SA Sieve Analysis El Expansion Index I -IA Hydrometer R-Val Resistance Value Proposed Elevation: 45.5 feet Depth to Water: N/A SE Sand Equivalent Chi Soluble Chlorides P1 Plasticit i Index Res H&Resistivitv Z C z hi Pa 1Z RI Z 0 SUMMARY OF SUBSURFACE CONDITIONS hi z " z Mc' (based on Unified Soil Classification System) hi hi us us z a -z C0 ..- Cl-i RI hi Pa us us N' 0 45 SM Old Paralic Deposits (Oop67): Reddish-brown, moist, loose to — — — — — — — - - medium dense, fine- to medium-grained, SILTY SAND Minor roots -- 018 inches. Medium dense to dense. - 5 —-40 - — Log terminated at 5 feet. — — — -- — — 10-- 35 15-- 30 20- - 25 25- - 20 30- -15 Symbol Legend PROPOSED ATHLETIC FIELD IMPROVEMENTS Groundwater Army and Navy Academy, Carlsbad, California Apparent Seepage CHRISTIAN WHEELER BY: MAh DATE: August 2012 No Sample Recovety E N C I N E E 1k I N C ** Erroneuus Blow Count 2120311.02R FJOB PLATE NO.: 10 (rocks present)NO.: LABORATORY TEST RESULTS PROPOSED ATHLETIC FIELD IMPROVEMENTS ARMY NAVY ACADEMY CARLSBAD BOULEVARD CARLSBAD, CALIFORNIA MAXIMUM DRY DENSITY AND OPTIMUM MOISTURE CONTENT (ASTM D1557) Sample Location Boring B-i @ 0-5%' Sample Description Light Brown Silty Sand, SM Maximum Density 131.5 pcf Optimum Moisture 8.2% DIRECT SHEAR (ASTM D3080) Sample Location Boring B-i @ 0-5'/2' Sample Type Remolded to 90 % Friction Angle 34° Cohesion 200 psf Boring B-6 @ 0-5' Orangish- Brown Silty Sand, SM 135.9 pcf 7.4% Boring B-6 @ 0-5' Remolded to 90 % 30° 150 psf [iJ EXPANSION INDEX TEST (ASTM D4829). Sample Location Boring B-i @ 7'- i' Initial I\ioisture: 10.4% Initial Dry Density 104.1 pcf Final Moisture: 27.2 % Expansion Index: 82 Medium) Boring B-3 @ 7.9% 108.8 pcf 18.1 % 1 (Very Low) GRAIN SIZE DISTRIBUTION (ASTM D422) Sample Location Sieve Sze #4 #8 #16 #30 #50 #100 #200 Boring B-4 @ 4'- 9' Percent Passing 100 98 96 90 66 47 27 Boring B-6 @ 0-5' Percent Passing 100 99 99 93 63 36 26 CWE 2120311.02R August 6, 2012 Plate No. 11 0 LABORATORY TEST RESULTS (CONTINUED) COLLAPSE POTENTIAL (ASTM D 5333) Sample Location Boring B-2 @ 6' Boring B-3 @ 11' Initial Moisture Content 8.5% 9.3% Initial Density 129.0 pcf 111.5 pcf Consolidation Before Water Added 1.7% 2.0% Consolidation After Water Added 1.8% 2.7% Final Moisture 9.3% 14.4% SOLUBLE SULFATES (CALIFORNIA TEST METHOD 417) Sample Location Boring B-3 @ 4'- 9' Soluble Sulfate 0.003 % (SO4) R-VALUE (CALIFORNIA TEST METHOD 301) Sample Location R-Value Boring B-8 @ @ 0-5' 57 CWE 2120311.02R August 6, 2012 Plate No. 12 CWE 2120311.02R August 6, 2012 Appendix A, Page A-i REFERENCES Anderson, J.G., Rockwell, R.K. and Agnew, D.C., 1989, Past and Possible Future Earthquakes of Significance to the San Diego Region, Earthquake Spectra, Volume 5, No. 2, 1969. California Division of Mines and Geology, 1997, Guidelines for Evaluating and Mitigating Seismic Hazards in California, CDMG Special Publication 117, adopted March 17, 1997. California Division of Mines and Geology, 1998, Maps of Known Active Fault Near Source-Zones in California and Adjacent Portions of Nevada. California Emergency Management Agency, 2009, Tsunami Inunciation Map for Emergency Planning, San Luis Rey Quadrangle, scale 1:24,000, June 1, 2009. Hart, E. W. and Bryant, W. A., 1997, Fault-Rupture Hazard Zones in California; California Division of Mines and Geology Special Publication 42. Jennings, C.W., 1975, Fault Map of California, California Division o Mines and Geology, Map No. 1, Scale 1:750,000. S Kennedy, M.P. and Tan, S.S., 2005, Geologic Map of the Oceanside 30'X 60' Quadrangle, California; California Department of Conservation and California Geological Survey. Kern, P., 1989, Earthquakes and Faults in San Diego County, Pickle Press, 73 pp. Tan, S.S., 1995, Landslide Hazards in the Northern Part of the San Diego Metropolitan Area, San Diego County, California, California Division of Mines and Geology Open-File Report 95-04. Tan, S.S. and Kennedy, M.P., 1996, Geologic Map of the Oceanside, San Luis Rey, and San Marcos 7.5' Quadrangles, San Diego County, California, California Division of Mines and Geology Open-File Report 96-02. United States Geologic Survey, Seismic Design Values for Buildings, Java Ground Motion Calculator Version 5.1.0. \Vesnousky, S.G., 1986, "Earthquakes, Quaternary Faults, and Seisrric Hazards in California," inJournal of Geophysical Research, Vol. 91, No. B12, pp 12,587 to 12,631, November 1986. TOPOGRAPHIC MAPS San Diego County, 1975, Map Sheet 362-1659; Scale: 1 inch = 200 feet. United States Geological Survey, 1967, San Luis Rey Quadrangle; Scale 1 inch = 2000 feet CWE 2120311.02R August 6, 2012 Appendix A, Page A-2 0 United States Geological Survey, 1975, San Luis Rey Quadrangle; Scale 1 inch = 2000 feet PHOTOGRAPHS Lenska's Aerial Atlas, 1994, The Thomas Guide, Sheet 1106. San Diego County, 1928, Flight 22A; Scale: 1 inch = 1000 feet (approximate). San Diego County, 1970, Flight 2, Photographs 2 through 4; Scale: 1 inch = 1500 feet (approximate). San Diego County, 1973, Flight 37, Photographs 1 and 2; Scale: 1 inch = 1000 feet (approximate). San Diego County, 1978, Flight 12B, Photographs 2 and 23; Scale 1 inch = 1000 feet (approximate). San Diego County, 1983, Photographs 254 and 255; Scale: 1 inch = 2000 feet (approximate. USDA, 1953, Flight 14M, Photographs 21 and 22; Scale: 1 inch = 1700 feet (approximate). 0 CWE 2120311.02R August 6, 2012 Appendix B, Page B-i RECOMMENDED GRADING SPECIFICATIONS - GENERAL PROVISIONS PROPOSED ATHLETIC FIELD IMPROVEMENTS ARMY NAVY ACADEMY CARLSBADBOULEVARD CARLSBAD, CALIFORNIA GENERAL INTENT The intent of these specifications is to establish procedures for clearing, compacting natural ground, preparing areas to be filled, and placing and compacting fill soils to the lines and grades shown on the accepted plans. The recommendations contained in the preliminary geotechnical investigation report and/or the attached Special Provisions are a part of the Recommended Grading Specifications and shall supersede the provisions contained hereinafter in the case of conflict. Tiese specifications shall only be used in conjunction with the geotechnical report for which they are a ?art. No deviation from these specifications will be allowed, except where specified in the geotechnical rep rt or in other written communication signed by the Geotechnical Engineer. 0 OBSERVATION AND TESTING Christian Wheeler Engineering shall be retained as the Geotechnical Engineer to observe and test the earthwork in accordance with these specifications. It will be necessary that the Geotechnical Engineer or his representative provide adequate observation so that he may provide his opinion as to whether or not the work was accomplished as specified. It shall be the responsibility of the contractor to assist the Geotechnical Engineer and to keep him apprised of work schedules, changes and new information and data so that he may provide these opinions. In the event that any unusual conditions not covered by the special provisions or preliminary geotechnical report are encountered during the grading operations, the Geotechnical Engineer shall be contacted for further recommendations. If, in the opinion of the Geotechnical Engineer, substandard conditions are encountered, such as questionable or unsuitable soil, unacceptable moisture content, inadequate compaction, adverse weather, etc., construction should be stopped until the conditions are remedied or corrected or he shall recommend rejection of this work. Tests used to determine the degree of compaction should be performed in accordance with the following 0 American Society for Testing and Materials test methods: CWE 2120311.02R August 6, 2012 Appendix B, Page B-2 Maximum Density & Optimum Moisture Content - ASTM D-1557-91 Density of Soil In-Place - ASTM D-1 556-90 or ASTM D-2922 All densities shall be expressed in terms of Relative Compaction as determined by the foregoing ASTM testing procedures. PREPARATION OF AREAS TO RECEIVE FILL All vegetation, brush and debris derived from clearing operatiDns shall be removed, and legally disposed of. All areas disturbed by site grading should be left in a neat and finished appearance, free from unsightly debris. After clearing or benching the natural ground, the areas to be filled shall be scarified to a depth of 6 inches, brought to the proper moisture content, compacted and tested for the specified minimum degree of compaction. All loose soils in excess of 6 inches thick should be removed to firm natural ground which is defined as natural soil which possesses an in-situ density of at least 90 percent of its maximum dry density. S When the slope of the natural ground receiving fill exceeds 20 percent (5 horizontal units to 1 vertical unit), the original ground shall be stepped or benched. Benches shall be cut to a firm competent formational soil. The lower bench shall be at least 10 feet wide or 1-1/2 times the equipment width, whichever is greater, and shall be sloped back into the hillside at a gradient of not less than two (2) percent. All other benches should be at least 6 feet wide. The horizontal portion of each bench shall be compacted prior to receiving fill as specified herein for compacted natural ground. Ground slopes flatter than 20 percent shall be benched when considered necessary by the Geotechnical Engineer. Any abandoned buried structures encountered during grading operations must be totally removed. All underground utilities to be abandoned beneath any proposed structure should be removed from within 10 feet of the structure and properly capped off. The resulting depressions from the above described procedure should be backfilled with acceptable soil that is compacted to the requirements of the Geotechnical Engineer. This includes, but is not limited to, septic tanks, fuel tanks, sewer lines or leach lines, storm drains and water lines. Any buried structures or utilities not to be abandoned should be brought to the attention of the Geotechnical Engineer so that he may determine if any special recommendation will be necessary. All water wells which will be abandoned should be backfilled and capped in accordance to the requirements set forth by the Geotechnical Engineer. The top of the cap should be at least 4 feet below finish grade or 3 CWE 2120311.02R August 6, 2012 Appendix B, Page B-3 feet below the bottom of footing whichever is greater. The type of cap will depend on the diameter of the well and should be determined by the Geotechnical Engineer and/or a qualified Structural Engineer. FILL MATERIAL Materials to be placed in the fill shall be approved by the Geotechnical Engineer and shall be free of vegetable matter and other deleterious substances. Granular soil shall contain sufficient fine material to fill the voids. The definition and disposition of oversized rocks and expansive or detrimental soils are covered in the geotechnical report or Special Provisions. Expansive soils, soils of poor gradation, or soils with low strength characteristics may be thoroughly mixed with other soils to provide satisfactory fill material, but only with the explicit consent of the Geotechnical Engineer. Any import material shall be approved by the Geotechnical Engineer before being brought to the site. PLACING AND COMPACTION OF FILL Approved fill material shall be placed in areas prepared to receive fill in layers not to exceed 6 inches in compacted thickness. Each layer shall have a uniform moisture content in the range that will allow the compaction effort to be efficiently applied to achieve the specified degree of compaction. Each layer shall be S uniformly compacted to the specified minimum degree of compaction with equipment of adequate size to economically compact the layer. Compaction equipment should either be specifically designed for soil compaction or of proven reliability. The minimum degree of compaction to be achieved is specified in either the Special Provisions or the recommendations contained in the preliminary geotechnical investigation report. When the structural fill material includes rocks, no rocks will be allowed to nest and all voids must be carefully filled with soil such that the minimum degree of compaction recommended in the Special Provisions is achieved. The maximum size and spacing of rock permitted in structural fills and in non- structural fills is discussed in the geotechnical report, when applicable. Field observation and compaction tests to estimate the degree of compaction of the fill will be taken by the Geotechnical Engineer or his representative. The location and frequency of the tests shall be at the Geotechnical Engineer's discretion. When the compaction test indicates that a particular layer is at less than the required degree of compaction, the layer shall be reworked to the satisfaction of the Geotechnical Engineer and until the desired relative compaction has been obtained. CWE 2120311.02R August 6, 2012 Appendix B, Page B-4 Fill slopes shall be compacted by means of sheepsfoot rollers or other suitable equipment. Compaction by sheepsfoot roller shall be at vertical intervals of not greater than four feet. In addition, fill slopes at a ratio of two horizontal to one vertical or flatter, should be trackrolled. Steeper fill slopes shall be over-built and cut- back to finish contours after the slope has been constructed. Slope compaction operations shall result in all fill material six or more inches inward from the finished face of the slope having a relative compaction of at least 90 percent of maximum dry density or the degree of compaction specified in the Special Provisions section of this specification. The compaction operation on the slopes shall be continued until the Geotechnical Engineer is of the opinion that the slopes will be surficially stable. Density tests in the slopes will be made by the Geotechnical Engineer during construction of the slopes to determine if the required compaction is being achieved. Where failing tests occur or other field problems arise, the Contractor will be notified that day of such conditions by written communication from the Geotechnical Engineer or his representative in the form of a daily field report. If the method of achieving the required slope compaction selected by the Contractor fails to produce the necessary results, the Contractor shall rework or rebuild such slopes until the required degree of compaction is obtained, at no cost to the Owner or Geotechnical Engineer. CUT SLOPES The Engineering Geologist shall inspect cut slopes excavated in rock or lithified formational material during the grading operations at intervals determined at his discretion. If any conditions not anticipated in the preliminary report such as perched water, seepage, lenticular or confined strata of a potentially adverse nature, unfavorably inclined bedding, joints or fault planes are encountered during grading, these conditions shall be analyzed by the Engineering Geologist and Geotechnical Engineer to determine if mitigating measures are necessary. Unless otherwise specified in the geotechnical report, no cut slopes shall be excavated higher or steeper than that allowed by the ordinances of the controlling governmental agency. ENGINEERING OBSERVATION Field observation by the Geotechnical Engineer or his representative shall be made during the filling and compaction operations so that he can express his opinion regarding the conformance of the grading with acceptable standards of practice. Neither the presence of the Geotechnical Engineer or his representative or CWE 2120311.02R August 6, 2012 Appendix B, Page B-5 the observation and testing shall release the Grading Contractor from his duty to compact all fill material to the specified degree of compaction. SEASON LIMITS Fill shall not be placed during unfavorable weather conditions. When work is interrupted by heavy rain, filling operations shall not be resumed until the proper moisture content and density of the fill materials can be achieved. Damaged site conditions resulting from weather or acts of God shall be repaired before acceptance of work. RECOMMENDED GRADING SPECIFICATIONS - SPECIAL PROVISIONS RELATIVE COMPACTION: The minimum degree of compaction to be obtained in compacted natural ground, compacted fill, and compacted backfill shall be at least 90 percent. For street and parking lot subgrade, the upper six inches should be compacted to at least 95 percent relative compaction. EXPANSIVE SOILS: Detrimentally expansive soil is defined as clayey soil which has an expansion index of S 50 or greater when tested in accordance with the Uniform Building Code Standard 29-2. OVERSIZED MATERIAL: Oversized fill material is generally defined herein as rocks or lumps of soil over 6 inches in diameter. Oversized materials should not be placed in fill unless recommendations of placement of such material should be provided by the Geotechnical Engineer. At least 40 percent of the fill soils shall pass through a No. 4 U.S. Standard Sieve. TRANSITION LOTS: Where transitions between cut and fill occur within the proposed building pad, the cut portion should be undercut a minimum of one foot below the base of the proposed footings and recompacted as structural backfill. In certain cases that would be addressed in the geotechnical report, special footing reinforcement or a combination of special footing reinforcement and undercutting may be required. 0