GEOTECHNICAL INVESTIGATION. Proposed WONDERLAND MONTESSORI ACADEMY Legacy Drive Prosper, Texas PROJECT NO. 18-DG9174.

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1 GEOTECHNICAL INVESTIGATION Proposed WONDERLAND MONTESSORI ACADEMY PROJECT NO. 18-DG9174 Prepared for: Mr. SANJAY JOSHI Flower Mound, Texas Prepared by: GEOSCIENCE ENGINEERING & TESTING, INC. Dallas, Texas June, Satsuma Drive, Suite 400 Dallas, Texas (P)

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3 CONTENTS INTRODUCTION Project Description... 1 Site Description... 1 Purposes and Scope of Work... 1 Report Format... 1 FIELD INVESTIGATION... 2 LABORATORY TESTING... 2 Review... 3 GENERAL SUBSURFACE CONDITIONS Stratigraphy... 3 Subsurface Water Conditions... 4 ANALYSIS AND RECOMMENDATIONS Construction Consultation and Monitoring... 4 Soil Movement... 4 FOUNDATION RECOMMENDATIONS... 5 A. Straight Shaft Piers... 5 Soil Induced Uplift Loads... 6 Pier Installation... 6 B. Shallow Foundation System... 6 Grade Beams... 7 Floor Systems... 8 Building Pad Preparation Select Fill Flex Base PAVEMENT AND SUBGRADE SITE GRADING and DRAINAGE CLOSURE ILLUSTRATIONS LOCATION PLAN... A BORING LOGS GEOSCIENCE, Inc.

4 INTRODUCTION Project Description This report presents the results of a Geotechnical Investigation performed by our firm at the referenced project located in. Based on the project information provided, it is our understanding that construction will consist of a Montessori academy and associated parking and driveway area. Information regarding structural loads was not available at the time of this investigation; however, we anticipate the loads will be light. It is expected that the finished floor elevation of the proposed building will be above the surrounding surfaces. Grading plans and other information regarding the referenced project were not available at the time of this investigation. Site Description The site of the referenced project is located east side and far north side of US 380 in the City of. At the time of this investigation, the site was vacant land covered with native vegetation and trees. The general location and orientation of the site is shown in the Illustrations section of this report. Purposes and Scope of Work The principal purposes of this investigation were to 1). Develop subsurface soil and rock stratigraphy at the boring locations; 2). Evaluate soil swell potential and provide alternatives to reduce soil movement; 3). Provide recommendations for foundation design parameters; 4). Provide pavement recommendations and 5). Provide site preparation recommendations Report Format The first sections of this report describe the field and laboratory phases of the study. The remaining sections present our engineering analysis that was used to develop geotechnical parameters for the type of foundation system proposed for this site. Boring logs and laboratory test results are presented in the Illustrations section of this report. GEOSCIENCE, Inc

5 FIELD INVESTIGATION The field portion of this investigation involved drilling and sampling a total of five (5) test borings. Test borings B-1 and B-2 were drilled to a depth of 30 feet below ground surface in the proposed building pad area and test borings B-3 to B-5 were drilled to a depth of 5 feet in the proposed paved area. The approximate locations of the borings are indicated on Plate A in the Illustrations Section of this report. Boring logs with descriptions of the soils sampled are attached on Plates 1 and 5. Soil strata boundaries shown on the boring logs are approximate. The borings were advanced using continuous flight auger techniques. Undisturbed cohesive soil samples were obtained using a 3-inch diameter thin-walled tube sampler pushed into the soils. The un-drained compressive strength of cohesive soils was estimated in the field using a calibrated pocket penetrometer. To evaluate the relative density and consistency of harder formations, Texas Department of Transportation Cone Penetrometer tests were performed at selected locations. The actual test consists of driving a three-inch diameter cone with a 170-pound hammer freely falling 24 inches. In relatively soft materials, the penetrometer cone is driven one foot and the number of blows required for each six-inch penetration is tabulated at respective test depths, as blows per six inches on the boring log. In hard materials, the penetrometer cone is driven with the resulting penetrations, in inches, accurately recorded for the first and second 50 blows for a total of 100 blows. The penetration for the total 100 blows is recorded at the respective testing depths on the boring log. All soil samples were removed or extruded from the samplers in the field, visually classified, and placed in appropriate containers to prevent loss of moisture or disturbance during transfer to the laboratory. The borings were advanced using dry auger procedures to observe the water level at the time of the exploration. These water level observations are recorded on the boring logs. LABORATORY TESTING Engineering properties of the foundation soils were evaluated in the laboratory by tests performed on representative soil samples, a series of moisture contents were performed to develop soil moisture profiles at the boring locations and to aid in evaluating the uniformity of soil conditions. Plastic and liquid limit (Atterberg limits), dry unit weight determinations and percentage passing number 200 sieve tests were performed on selected samples from the GEOSCIENCE, Inc

6 borings to confirm visual classification and to evaluate soil volume change potentials. Shear strengths of cohesive soils were estimated by field pocket penetrometer and laboratory unconfined compression tests performed on selected samples. The results of these tests are presented on the boring logs. Review Descriptions of subsurface materials obtained in the field at the time the boring was drilled were modified in accordance with results of laboratory tests and visual examination in the laboratory. All recovered soil samples were examined and classified in accordance with ASTM D 2487 and described as recommended in ASTM D 2488 and the Unified Soil Classification procedures. Classification of the soils and finalized material descriptions are shown on the boring logs. GENERAL SUBSURFACE CONDITIONS Stratigraphy Based on our interpretation of the borings drilled for this investigation, the subsurface stratigraphy at this site consists predominately of clay soils underlain by shaly clay soils deeper by gray shale. More specifically, the subsurface stratigraphy encountered within the depths of the test borings drilled for this study consisted of: Dark brown followed CLAY (CH) soils with calcareous nodules from existing ground surface elevation to a depth of 7 to 8 feet in test borings B-1 and B-2, and to the completion depth of shallower test borings B-3 to B-5 drilled. Below 7 to 8 feet in test borings B-1 and B-2, tan CLAY (CH) soils with calcareous nodules and gravel seams were encountered and remained visible to a depth of 11 to 12 feet in test borings B-1 and B-2 drilled, below which, gray and tan/tan and gray SHALY CLAY (CH) soils with calcareous nodules were encountered and remained visible to a depth of 21 to 24 feet in the deeper drilled test borings. At 21 to 24 feet in test borings B-1 and B-2, gray weathered SHALE was encountered and remained in evidence to the completion depths of test borings B-1 and B-2 drilled. Detailed descriptions of the subsurface stratigraphies encountered at this site are presented on the boring logs in the Illustrations Section of this report. GEOSCIENCE, Inc

7 Subsurface Water Conditions The borings were advanced using dry auger drilling procedures in order to observe any groundwater seepage levels. At the time of this investigation, groundwater seepage was encountered to a depth of 12 feet during drilling and 28.5 feet upon completion of drilling in test borings B-1 and B-2 drilled. NO groundwater seepage was encountered in the shallower test borings B-3 to B-5 drilled at the time of this study. It should be noted however that future construction activities may alter the surface and subsurface drainage characteristics of this site. As such, we suggest re-verifying the depth to groundwater just prior to and during construction. If there is a noticeable change from the conditions reported herein, this office should be notified immediately to review the effect that it may have on the design recommendations. Based on short-term observations, it is not possible to accurately predict the magnitude of subsurface water fluctuations that might occur. Also water seepage may encounter within the fractures of the soils particularly after a period of heavy rainfall. ANALYSIS AND RECOMMENDATIONS Construction Consultation and Monitoring We recommend that GETI be given an opportunity to review the final design drawings and specifications to ensure that the recommendations provided in this report have been properly interpreted. Wide variations in soil conditions are known to exist between the boring locations, particularly in the vicinity of this site. Further, unanticipated variations in subsurface conditions may become evident during construction. During the excavation and foundation phases of the project, we recommend that a reputable Geotechnical Engineering firm be retained to provide construction surveillance services in order to 1) observe compliance with the geotechnical design concepts, specifications and recommendations, and 2) observe subsurface conditions during construction to verify that the subsurface conditions are as anticipated, based on the boring performed for this investigation. Geoscience is available to perform the aforementioned services. Soil Movement The near surface subgrade soils encountered at this site exhibited plasticity indices between 49 and 62. These type soils are considered as extremely highly expansive in nature and are capable GEOSCIENCE, Inc

8 of significant vertical and horizontal ground movements due to soil swell and shrinkage which occurs with changes in soil moisture content(s). The magnitude of the movements experienced by the foundation will depend on one or a combination of several factors including the moisture content and the depth at which plastic soils are encountered at the time of construction, soil plasticity, rainfall moisture index, local drainage characteristics, and other related factors. Potential Vertical Movement was calculated using Texas Department of Transportation method (TxDOT 124-E). Based on the aforementioned method, the potential vertical rise (PVR) is estimated to be 2.75 to 3.5 inches at the existing surface of the locations of borings drilled at the time of this investigation. However; in the event that DRY CONDITIONS exist at the time of construction then the PVR will be on the order of 6.25 to 6.75 inches. Considerably more movement will occur in areas where water ponding is allowed to occur during and/or after construction or- fill soils other than select fill soils are planned for use. Site grading may also increase the potential for movement. Deep seated shaly clay soils can also increase the soils potential vertical rise. We recommend that the PVR should be re-evaluated at the time of construction. FOUNDATION RECOMMENDATIONS The site is located in the Eagle Ford Formation and west of Preston Road. The soils in this region are known to contain some concentrations of soluble sulfate. Sulfate resistance concrete should be used for all the foundation construction. A. Straight Shaft Pier Type Foundation System The structural loads can be supported by auger excavated straight-sided, cast-in-place, reinforced concrete piers. The piers should be founded at 3 feet within gray weathered shale encountered at a depth of 21 to 24 feet at the location of deeper drilled test borings. The net allowable end bearing capacity of 14,000-psf and skin friction of 1,800 psf in compression and 1,500 psf in tension can be used. The skin friction component should only be applied to the portion of the shaft located in the bearing material below the recommended minimum penetration. We recommend that our firm should monitor the pier drilling operation in order to assure that the pier has been installed within weathered shale stratum. GEOSCIENCE, Inc

9 Soil Induced Uplift Loads The drilled shafts will be subjected to some uplift loads due to heaving in the overlying clay soils. The uplift loads can be approximated by assuming a uniform uplift of 1,600 psf over the shaft perimeter of 10 feet of the pier length for current moisture and 2,000 psf in the event that DRY CONDITIONS exist at the time of construction. The uplift pressure can be neglected for the depth of select fill if placed to reduce the soil swell potential and can be reduced to 1,000 psf for moisture conditioned and chemical or water pressure injected soils. To resist the net tensile load, the shaft must contain sufficient continuous vertical reinforcement to the full depth of the pier. Foundation piers designed and constructed in accordance with the information provided in this report will have a factor of safety in excess of 2.5 against shear type failure and will experience minimal settlement (less than one inch). Pier Installation The construction of all piers should be observed by experienced geotechnical personnel during construction to ensure compliance with design assumptions and to verify: (1) the bearing stratum; (2) the minimum penetration; (3) the removal of all smear zones and cuttings; (4) that groundwater seepage is correctly handled; and (5) that the shafts are vertical and within acceptable tolerance levels. Our Firm is available to provide these services upon request. Reinforcing steel and concrete should be placed immediately after the excavation has been completed and observed. In no event should a pier excavation be allowed to remain open for more than 8 hours. Concrete should be placed in such a manner to prevent segregation of the aggregates. Subsurface conditions at the time our borings were advanced indicate that temporary casing will be required for straight shaft piers only. B. Shallow Footings The foundation of the proposed building can also be supported by spread footings. The spread footings should be installed at a minimum depth of 2.5 feet from the finished floor elevation installed within the moisture conditioned or chemical or water pressure injected soils or density controlled select fill soils. The spread footings can be designed using a net allowable bearing pressure of 2,500 psf for select fill soils (a minimum of 2 feet of select fill soils is required below the GEOSCIENCE, Inc

10 spread footing installation depth). A net allowable bearing capacity of 2,000 psf can be used for moisture conditioned and chemical or water pressure injected soils. These values include a factor of safety of 2.5 with respect to the un-drained shear strength of the foundation soils. The bottom of the spread footings should be free of any loose and/or soft materials prior to concrete placement. Any areas at the bottom of the footings where soft spots are noted we recommend: a) the bottom of the grade beams either be rolled or compacted by re-working with the optimum moisture with a hand compactor. Each foundation excavation should be evaluated by a geotechnical engineer to ensure that the foundation bears within hard stratum - Or - b) reduce the allowable soil bearing capacity. At the time of such evaluation, it may be necessary to perform compaction testing or hand penetrometer probe test in the base of the foundation excavation to assure that the above recommendations are adhered. Grade Beams Grade beams should be structurally connected into the top of the piers or spread footings. The soil swell potential should be reduced to less than an inch by moisture conditioning method or chemical or water pressure injection or placement of select fill soils as per the procedures outlined in later sections of this report. Alternatively, the grade beam cam be suspended in conjunction with piers (most positive option). A minimum void space of 10 inches should be provided beneath the grade beams. This void space allows movement of the soils below the grade beams without distressing the structural system. Structural cardboard forms are typically used to provide this void beneath grade beams. Cardboard forms must have sufficient strength to support the concrete grade beams during construction. Our previous experiences indicate that major distress in the grade beams will occur if the integrity of the void box is not maintained during and after construction. The excavation that the void box lays in must remain dry. Cardboard cartons can easily collapse during concrete placement if the cardboard becomes wet. Backfill material must not be allowed to enter the carton area below grade beams as this reduces the void space which underlying soils need to swell. GEOSCIENCE, Inc

11 Floor Systems In conjunction with piers, two types of floor systems may be considered for use at this site: i) Suspended Floor System (most positive option) - The most positive floor system for pier type foundation systems in areas with expansive soils consists of a suspended floor system. The floor system of the proposed building should be structurally supported on the foundation piers and a minimum void space of 10 inches should be provided between the bottom of the slab and the underlying soils. ii) Ground Supported Slab - A ground-supported slab may be considered for use at this site, provided the risk of some post-construction movement is acceptable. The slab may be of a grid-type grade beam and slab reinforced with conventional rebar type foundation system. A ground-supported slab, if used, then the PVR should be reduced to one inch by adopting one of the following methods: Moisture conditioning method: (re-evaluation of moisture is required prior to adapting this method or dry condition should be assumed) Remove the subgrade soils to a depth of 8 feet for the current moisture profile and 12 feet (for dry condition) below the finished grade elevation and stockpile. The exposed surface should be watered and proof- rolled with heavy equipment. The previously removed soils should be placed back in the building pad area in 6 to 8 inches loose lifts and mixed thoroughly to form a homogenous consistent soil and each lift should be compacted to between 93 and 98 percent of the maximum standard proctor dry density with a minimum moisture content of 4 points above optimum. We recommend the improvements extend an additional five feet beyond the perimeter of the building pad and should include all the areas sensitive to the movement. The upper 2.5 feet or 6 inches below the grade beam depth of the soils should consist of select fill soils or- flex base materials. In the event that select fill soil is planned to be used as a cap, then it should be placed in 6 to 8 inches loose lifts and compacted between 95 and 100 percent of the maximum dry density as per ASTM D 698 with moisture contents within three points of optimum moisture as per ASTM D 698. We recommend select fill soils not be extended beyond the building line however; the perimeter outside the grade beam should be capped with high plasticity index clay soils in order to retard any water seepage underneath the foundation. GEOSCIENCE, Inc

12 If the flex base is used as a cap atop of moisture conditioned soils, then the flex base should be placed in 6 to 8 inches loose lifts compacted to a minimum of 98 percent of maximum dry density as per ASTM D 698 and the moisture content should be between -2 to +3 percent points above optimum. Field density tests should be taken at the rate of at least one test per each 2,500 square feet, per lift, in the area of all compacted fill. For areas where hand tamping is required, the testing frequency should be increased to approximately one test per lift, per 100 linear feet of area. Construction of the building slab should start shortly upon completion of the subgrade improvement process. Moisture loss of the improved soils should not be allowed to occur between the time the improvement procedures are completed and the start of the construction. -OR- Chemical or water pressure injection: (re-evaluation of moisture is required prior to adapting this method or dry condition should be assumed) The potential vertical movement can be reduced to one inch by chemical or water pressure injection method. The entire building pad should be undercut to a minimum depth of 2.5 feet below the finished grade then chemical or water pressure injection to the subgrade soils should be performed to a depth of 8 feet (for current condition) and 12 feet (for dry condition) below the finished grade. For improvement of subgrade soils by chemical or water pressure injection, we recommend extending the building pad to an additional 5 feet beyond the building line and should cover all areas that are sensitive to soil movement. The number of injections required generally depends on: the rate at which the soils absorb chemical or water, initial moisture condition and hardness of the soils, and the amount of reduction that is desired and can be tolerated by the slab foundation. We recommend at a minimum of 4 passes of chemical or water pressure injection should be performed prior to the testing. Upon completion of chemical or water pressure injection, post-injection testing will be required to ensure that the swell potential of the soils has been adequately reduced for the design of the slab foundation. A full-time laboratory technician from our Firm should be present throughout the injection operations. Undisturbed GEOSCIENCE, Inc

13 samples should be obtained at every one-foot interval to the total injected depth from 1 test hole per 5,000 square foot. Adjustments in the testing program should be at the discretion of the testing engineer. A minimum of 3 free swell tests should be performed per test hole. Samples will be tested at the approximate overburden pressure of the sample depth. The injected subgrade should then be sealed with 2.5 feet of select fill soils -or- flex base. Select fill soils should be placed in 6 to 8 inches loose lifts and compacted between 95 and 100 percent of maximum dry density as per ASTM D 698 with moisture contents within three points of optimum moisture as per ASTM D 698. We recommend select fill soils should not be extended beyond the building line however; the perimeter outside the grade beam should be capped with high plasticity index clay soils in order to retard any water seepage underneath the foundation. If the flex base is used as a cap atop of moisture conditioned soils, then the flex base should be placed in 6 to 8 inches loose lifts compacted to a minimum of 98 percent of maximum dry density as per TX113 and the moisture content should be between -2 to +3 percent points above optimum. Field density tests should be taken at the rate of at least one test per each 2,500 square feet, per lift, in the area of all compacted fill. For areas where hand tamping is required, the testing frequency should be increased to approximately one test per lift, per 100 linear feet of area. Construction of the building slab should start shortly upon completion of the injection process. Construction of the building slab should start shortly upon completion of the injection process. Moisture loss of the injected soils should not be allowed to occur between the time the injection procedures are completed and the start of the construction. -OR- Placement of select fill soils: ((for current moisture condition) All the soils samples retrieved from the test borings appear to be near or above the optimum moisture value as such the current PVR is approximately 2.75 to 3.5 inches. In the event the building is constructed within 60 days from the date of the report then the PVR can be reduced to an inch by placement of select fill soils. GEOSCIENCE, Inc

14 The soils swell movement can be reduced to one inch by placement of 5 feet (for current moisture condition) of select fill below finished grade. As mentioned earlier that the uplift pressure can be neglected for the depth of select fill soils stratum if used. The bottom of the select fill soil (i.e. top of subgrade soils) should be scarified to a depth of 6 inches and compacted to 95 and 100 percent of the maximum dry density with moisture content of 4 points of optimum. Placement of expansive soils on the building pad will increase the potential for vertical movement; therefore, we recommend the use of select fill soils (specifications of which are outlined in the Select Fill Section of this report). The improvements should extend an additional 5 feet beyond the building line; however, the upper 2 feet or depth of the grade beam whichever is deeper of select fill should not extend beyond the building line but rather should be capped with on-site high plasticity index clay soils in order to resist water seepage into the subgrade soils. Select fill soils should be placed as per the procedure outlined in the Building pad preparation Section of this report. Field density tests should be taken at the rate of one test per every 2,500 square feet per lift, or a minimum of 3 tests per lift in the area of all compacted fill. For areas where hand tamping is required, the testing frequency should be increased to approximately one test per lift, per 100 linear feet of area. The grade beam should be a minimum of 2 feet deep and 12 inches wide and should be installed within compacted and tested select fill soils or moisture conditioned or chemical/water pressure injected soils. A net allowable bearing capacity of 1,500 psf can be used to design the grade beam and slab for the moisture conditioned and chemical or water pressure injected soils and 2,000 psf for select fill soils. A moisture barrier of polyethylene sheeting or similar type material should be placed between the slab and the subgrade soils to retard moisture migration through the slab. Grade beams and floor slabs should be adequately reinforced to minimize cracking as normal movements occur in the foundation soils. It should be understood that a soilsupported foundation system will experience some movement over time. Building Pad Preparation Prior to the placement of fill soils, all loose soils and any vegetation should be removed and disposed of the site until hard stratum is encountered. GEOSCIENCE, Inc

15 For a suspended floor system, after removal of all above referenced items, the exposed surface should be scarified to a minimum depth of 6 inches water as required and compacted between 95 and 100 percent of the maximum dry density as defined by ASTM D 698 (Standard Proctor Test) at a moisture content between optimum and 4 points above optimum. Additional fill, if required, should consist of clean on-site or off-site soils compacted to resist the initial concrete loads. Placement of select fill soils is not required for suspended floor system. For a ground supported floor system: upon removal of all the referenced above items, then the soils swell movement should be reduced to an inch or less by moisture conditioning method or chemical/water pressure injection method or by placement of select fill soils as per the procedures outlined in previous sections of this report. Additional fill, if is required, should consist of select fill soils only. Select fill materials should be placed in six (6) to eight (8)-inch loose lifts at moisture contents between optimum and 3 percentage points above optimum. Each lift compacted to between 95 and 100 percent of the maximum dry density as defined in ASTM D 698. Field density tests should be taken at the rate of one test per every 2,500 square feet per lift, or a minimum of 3 tests per lift in the area of all compacted fill. For areas where hand tamping is required, the testing frequency should be increased to approximately one test per lift, per 100 linear feet of area. Select Fill "Select fill," as referred to in this report, should consist of clayey sands free of organic materials with a Plasticity Index between 6 and 16, a Liquid Limit of 38 or less, and between 15 and 45 percent passing a No. 200 sieve. Placement and compaction of the select fill should be performed in accordance with the "Building Pad Preparation" section of this report. It is preferable to place the select fill above the surrounding ground surface. The provision of a subsurface drainage system will be required in areas where the select fill is placed below the surrounding ground surface. Flex Base TxDOT 247 -Type 1. GEOSCIENCE, Inc

16 PAVEMENT AND SUBGRADE General Specific wheel loading and traffic volume characteristics were not available at the time of this investigation. However, we have assumed that light passenger vehicle traffic will be most predominant in the parking areas and the relatively heavier fire truck traffic will occur in the drive areas area around and behind the structure, and in the fire lane. Based on assumed loading conditions, we have developed the following Portland cement concrete pavement design sections for use at this site. Light Traffic Minimum Thickness (inches) Portland Cement Concrete 5 Minimum Lime Stabilized Subgrade 6 Heavy Traffic Portland Cement Concrete 6 Minimum Lime Stabilized Subgrade 6 Prior to the placement of any fill in the pavement area, we recommend that all loose and fill (if any) soils and any vegetation should be removed and disposed of the site until hard stratum is encountered. The exposed surface should be scarified to a depth of 6 inches compacted to 95 and 100 percent of maximum dry density with water content between optimum and 4 points above optimum. Additional fill soil if is required, should consist of onsite natural clay soils. The fill soils should be compacted between 95 and 100 percent of the maximum dry density as defined by ASTM D 698 (Standard Proctor Test) at moisture content between optimum and 4 points above optimum. The upper 6 inches of the final grade in all the areas of the pavement should then be stabilized with lime. We estimate approximately 8 to 12 percent of hydrated lime (between 36 and 42 pounds of lime per square yard for 6-inch-thick soil) will be required to stabilize the subgrade soils (to reduce the plasticity index to 15 or less). It should be noted that after the final grade is GEOSCIENCE, Inc

17 complete, the actual amount of lime required should be calculated by lime series test in the laboratory. The site is located in the Eagle Ford Formation and west of Preston Road. The soils in this region are known to contain some concentrations of soluble sulfate. Given the fact that sulfate tends to negate the effects of lime, we recommend a Sulfate Analysis be performed on the finished grade of the paving area prior to lime stabilizing the subgrade. In the event that lime stabilization of the subgrade soils is not economically feasible or the sulfate concentration is higher than 1000 ppm, then the thickness of the concrete can be increased by an additional 1 inch or City recommended thickness as an alternative and Sulfate resistance concrete should be used for all the paving area. Design of the concrete pavement should specify a minimum 28-day concrete compressive strength of 3000 psi for all the pavement and 4000 psi for the fire lane with 4 percent to 6 percent entrained air. The concrete should be placed within one and one-half hours of batching. During hot weather, the concrete placement should follow ACI 311 Hot Weather concreting and in no case should the concrete temperature be allowed to exceed 95ºF. To avoid excessive heat periods, consideration should be given to limiting concrete placement to a time of day that will minimize large differences in the ambient and concrete temperature. Past experience indicates that pavements with sealed joints on 15 to 20-foot spacings, cut to a depth of at least one-quarter of the pavement thickness, generally exhibit less uncontrolled postconstruction cracking than pavements with wider spacings. As a minimum, expansion joints should be used wherever the pavement abut a structural element subject to a different magnitude of movement, e.g., light poles, retaining walls, existing pavement, building walls, or manholes. After construction, the construction and expansion joints should be inspected periodically and resealed, if necessary. The pavement should be reinforced using at least No. 3 bars, 24 inches on center, each way and for fire lane the rebar should be No. 4 rebars 24 inches c/c or city standards should be followed. GEOSCIENCE, Inc

18 SITE GRADING and DRAINAGE All grading should provide positive drainage away from the proposed structures and should prevent water from collecting or discharging near the foundations. Water must not be permitted to pond adjacent to the structures during or after construction. Surface drainage gradients should be designed to divert surface water away from the buildings and edges of pavements and towards suitable collection and discharge facilities. Unpaved areas and permeable surfaces should be provided with steeper gradients than paved areas. Pavement drainage gradients within 5 feet of buildings should be constructed with a minimum slope of one inch per foot to prevent negative drainage gradients (ponding water conditions) from developing due to differential upward pavement movements. Sidewalk drainage gradients should be along maximum slopes allowed by local codes. Roofs should be provided with gutters and downspouts to prevent the discharge of rainwater directly onto the ground adjacent to the building foundations. Downspouts should not discharge into any landscaped bed near the foundations. Downspouts should discharge directly into storm drains or drainage swales, if possible. Roof downspouts and surface drain outlets should discharge into erosion-resistant areas, such as paving or rock riprap. Recessed landscaped areas filled with pervious sandy loam or organic soil should not be used near the foundation. All trees should be a minimum of one-half their mature height away from the building or pavement edges to reduce potential moisture losses. Water permitted to pond in planters, open areas, or areas with unsealed joints next to structures can result in on-grade slab or pavement movements, which exceed those, indicated in this report. Exterior sidewalks and pavements will be subject to some post construction movement as indicated in this report. These potential movements should be considered during preparation of the grading plan. Flat grades should be avoided. Where concrete pavement is used, joints should be sealed to prevent the infiltration of water. Some post-construction movement of pavement and flatwork may occur. Particular attention should be given to joints around the building. These joints should be periodically inspected and resealed where necessary. GEOSCIENCE, Inc

19 CLOSURE It should be noted that some variations in soil and moisture conditions may exist between boring locations. Statements in this report as to subsurface variations over given areas are intended as estimations only, based upon the data obtained from specific boring locations. The results, conclusions, and recommendations contained in this report are directed at, and intended to be utilized within the scope of work outlined in this report. The report is not intended for use in any other manner. Geoscience Engineering and Testing, Inc., makes no claim or representation concerning any activity or condition falling outside the specified purposes for which this report is directed; said purposes being specifically limited to the scope of work as defined herein. Inquiries regarding scope of work, activities and/or conditions not specifically outlined herein, should be directed to GETI. The completed landscaping should be carefully inspected to verify that plantings properly drain. Soil in plantings may settle, which will tend to pond water, or plantings may block entrances to surface drains. Therefore, maintaining positive drainage from landscape irrigation will be an ongoing concern. GEOSCIENCE, Inc

20 ILLUSTRATIONS GEOSCIENCE, Inc.

21 Approximate Boring Location Project No. 18-DG9174 BORING LOCATION PLAN Proposed WONDERLAND MONTESSORU ACADEMY Plate A GEOSCIENCE, Inc.

22 DEPTH (ft.) 0 FIELD DATA SOIL & ROCK SYMBOL SAMPLE TYPE P: HAND PEN., TSF T: THD, BLOWS/FT. N: SPT, BLOWS/FT. P4.5 P3.0 STRATUM DEPTH (FT.) Location: See Location Plan Surface Elevation: Unknown Drilling Method: CFA LOG OF BORING NO. B-1 Proposed "Wondeland Montessori School" Date Boring Drilled: 05/29/2018 Completion Depth: 30 Groundwater Information: Seepage Encountered During Drilling: 12 Upon Completion: Dry Project No. 18-DG9174 DESCRIPTION OF STRATUM Dark brown CLAY (CH) with calcareous nodules WATER CONTENT, % LIQUID LIMIT PLASTIC LIMIT LABORATORY DATA PLASTICITY INDEX UNIT DRY WEIGHT (PCF) UNCONFINED STRENGTH (TSF) % PASSING NO. 200 SIEVE SOIL SUCTION TEST (TOTAL CM. OF WATER) P P P Tan CLAY (CH) with calcareous nodules and gravel seams -increase in gravel to 10' 9 Gray and tan SHALY CLAY (CH) with calcareous nodules 15 P with occasional gravel seams below 18' T100/ 4.2" 24 Gray weathered SHALE T100/ 4.5" REMARKS: TUBE SAMPLE AUGER SAMPLE SPLIT- SPOON ROCK CORE THD CONE PEN. NO RECOVERY Geoscience Engineering & Testing Plate 1

23 LOG OF BORING NO. B-2 Proposed "Wondeland Montessori School" DEPTH (ft.) 0 FIELD DATA SOIL & ROCK SYMBOL SAMPLE TYPE P: HAND PEN., TSF T: THD, BLOWS/FT. N: SPT, BLOWS/FT. P3.25 STRATUM DEPTH (FT.) Location: See Location Plan Surface Elevation: Unknown Drilling Method: CFA Date Boring Drilled: 05/29/2018 Completion Depth: 30 Groundwater Information: Seepage Encountered During Drilling: 12 Upon Completion: 28.5 Project No. 18-DG9174 DESCRIPTION OF STRATUM Dark brown CLAY (CH) with calcareous nodules WATER CONTENT, % 28 LIQUID LIMIT PLASTIC LIMIT LABORATORY DATA PLASTICITY INDEX UNIT DRY WEIGHT (PCF) UNCONFINED STRENGTH (TSF) % PASSING NO. 200 SIEVE SOIL SUCTION TEST (TOTAL CM. OF WATER) P P P Tan CLAY (CH) with calcareous nodules 10 P Tan and gray SHALY CLAY (CH) with calcareous nodules 15 P P Gray weathered SHALE 25 T100/ 4.5" T100/ 4.2" REMARKS: TUBE SAMPLE AUGER SAMPLE SPLIT- SPOON ROCK CORE THD CONE PEN. NO RECOVERY Geoscience Engineering & Testing Plate 1

24 LOG OF BORING NO. B-3 Proposed "Wondeland Montessori School" DEPTH (ft.) 0 FIELD DATA SOIL & ROCK SYMBOL SAMPLE TYPE P: HAND PEN., TSF T: THD, BLOWS/FT. N: SPT, BLOWS/FT. P4.5 STRATUM DEPTH (FT.) Location: See Location Plan Surface Elevation: Unknown Drilling Method: CFA Date Boring Drilled: 05/29/2018 Completion Depth: 5 Groundwater Information: Seepage Encountered During Drilling: None Upon Completion: Dry Project No. 18-DG9174 DESCRIPTION OF STRATUM Dark brown CLAY (CH) with calcareous nodules 20 WATER CONTENT, % LIQUID LIMIT PLASTIC LIMIT LABORATORY DATA PLASTICITY INDEX UNIT DRY WEIGHT (PCF) UNCONFINED STRENGTH (TSF) % PASSING NO. 200 SIEVE SOIL SUCTION TEST (TOTAL CM. OF WATER) P P P REMARKS: TUBE SAMPLE AUGER SAMPLE SPLIT- SPOON ROCK CORE THD CONE PEN. NO RECOVERY Geoscience Engineering & Testing Plate 3

25 LOG OF BORING NO. B-4 Proposed "Wondeland Montessori School" DEPTH (ft.) 0 FIELD DATA SOIL & ROCK SYMBOL SAMPLE TYPE P: HAND PEN., TSF T: THD, BLOWS/FT. N: SPT, BLOWS/FT. P2.75 STRATUM DEPTH (FT.) Location: See Location Plan Surface Elevation: Unknown Drilling Method: CFA Date Boring Drilled: 05/29/2018 Completion Depth: 5 Groundwater Information: Seepage Encountered During Drilling: None Upon Completion: Dry Project No. 18-DG9174 DESCRIPTION OF STRATUM Dark brown CLAY (CH) with calcareous nodules 31 WATER CONTENT, % LIQUID LIMIT PLASTIC LIMIT LABORATORY DATA PLASTICITY INDEX UNIT DRY WEIGHT (PCF) UNCONFINED STRENGTH (TSF) % PASSING NO. 200 SIEVE SOIL SUCTION TEST (TOTAL CM. OF WATER) P P P REMARKS: TUBE SAMPLE AUGER SAMPLE SPLIT- SPOON ROCK CORE THD CONE PEN. NO RECOVERY Geoscience Engineering & Testing Plate 4

26 DEPTH (ft.) 0 5 FIELD DATA SOIL & ROCK SYMBOL SAMPLE TYPE P: HAND PEN., TSF T: THD, BLOWS/FT. N: SPT, BLOWS/FT. P2.0 P1.0 P1.5 STRATUM DEPTH (FT.) P1.0 5 Location: See Location Plan Surface Elevation: Unknown Drilling Method: CFA LOG OF BORING NO. B-5 Proposed "Wondeland Montessori School" Date Boring Drilled: 05/29/2018 Completion Depth: 5 Groundwater Information: Seepage Encountered During Drilling: None Upon Completion: Dry Project No. 18-DG9174 DESCRIPTION OF STRATUM Dark brown CLAY (CH) with calcareous nodules 32 WATER CONTENT, % LIQUID LIMIT PLASTIC LIMIT LABORATORY DATA PLASTICITY INDEX UNIT DRY WEIGHT (PCF) UNCONFINED STRENGTH (TSF) % PASSING NO. 200 SIEVE SOIL SUCTION TEST (TOTAL CM. OF WATER) REMARKS: TUBE SAMPLE AUGER SAMPLE SPLIT- SPOON ROCK CORE THD CONE PEN. NO RECOVERY Geoscience Engineering & Testing Plate 5